Hi, I've posted here before with my full story about my IBS. I have IBS-D with a little IBS-C, anxiety is a huge trigger factor, greasy foods are particually troublesome, I might have Gluten Intolerance, I may be Lactose Intolerant, I've had 5 very bad months with my IBS, my symptoms are usually loose BM's, abdominal pains, gas, senstations of needing to "go", and cramps, I'm male, and I'm a teenager in high school.About 7 months ago my IBS got generally worse. It wasn't that I had more D or loose BMs than usual, it was that I had more gas, cramps, pains, and sensations to need to "go". Because of this, I did a complete overhaul of my eating habits. I started off doing something that probably wasn't a very smart idea; if I had a big event that I need to go to where my IBS would be a major problem (such as going to work, marching band) I would eat about half as much as I normally would on that day. That led to eating about half as much on the day of the event and the day before, and twice I ate only marginally the day before and I ate nothing on the day of the event until after the event, which would usually be at night. I did this because I believed that it would help to control my IBS and I figured that if I didn't eat, there would be absolutely no chance that I would have some D. This was a very bad time for me!The marching bad season ended 2 months later, so I never again "fasted" to that extreme. But, around that time I began not eating breakfast and or lunch, opting to instead drink a nutrition drink in the morning and waiting until school ended at 3 to eat an actual meal. I would eat a lot in the afternoons, to compensate. This lasted for a while, I don't remember how long exactly.Around this time I also changed up my diet a lot. I completely gave up on anything greasy, so no fried foods at all; I also gave up on butter and rich in fat foods. My diet consisted of mostly rice, breaded chicken, cereals, soy milk (chocolate flavored, yummy), bagels, breads, and nutrition drinks (lactose free); I was trying to follow the IBS: The First Year diet.About 3 months ago I began eating lunch again; I had aquired a lunch period during the school day where I could go home for lunch. This way I felt comfortable eating lunch because I could make what I needed, and I had a toilet that I had easy access to.Recently, my diet changed again; I took up the possibility that I may have a gluten allergy. So, all my bread products are now gluten and wheat free. I also stopped drinking soy milk in favor of rice and almond milk. This newest diet seems to be working wonderfully for me; I'm very, very regular, only need to have a BM 2-3 times a day, the sensations of needing to find a bathroom have been reduced, I have much much less gas and cramps, but strangely I now have a lot more pains in my abdominal area and I'm experiencing random bouts of minor constipation that don't last longer than a day.Well, I think I've run into some very bad trouble. 9 months ago, I weighed about 170. I was 6 feet tall. 6 months ago, when my IBS became worse and I took those drastic measures, I weighed about 165 or so. During the really bad 2 months follwing this I lost a bunch of weight. I think I once lost almost 5 pounds in 2 days, when I almost completely stopped eating for those 2 days. I think after those bad two months, I was somewhere hovering around 155 or so. 2 months after that, which is 2 months after I drastically changed my diet, I went down to yet consistently maintained 150. 2 months ago (about a month after I reached 150), I slowly started losing a little more and more weight. 6-5 weeks ago, I reached 145. Around this time (the last 2 months) I was eating lunch, but no breakfast. Now, it gets really creepy. 4 weeks ago, I reached a weight that terrified me - 140. I was very confused, very shocked, and very upset. I knew that it was not natural. So, I decided to take action. I began eating more, and more often. I tried eating breakfast again, but that ended very, very badly! Each day that I ate breakfast I had to go home sick from school because I was having D. It was very traumatizing, so I haven't eaten breakfast on a schoolday since. My weight then started crazily fluctuating. Sometimes, after I had a good weekend where I ate a lot, I weighed 145. Then, it would go back to 140 after the school week. One time, it dipped to 135 after I didn't eat breakfast the day before and I ate a smaller amount of food the day before. Seeing 135.... I was so, so disturbed. I was very confused, angry, shocked, even appalled. I gained back to 140 soon after. 2 days ago, I went down to 137, but now it's back to 140.This has been very confusing, very shocking, and very scary. Though, I don't really know a lot about what I'm supposed to weigh and about how much weight a person can lose in a span of time without hurting their body. Am I in big trouble here? Why is this happening? How do I get the weight back? I'm very, very scared!My body has changed as I've dipped under 150. I notice how thin my arms are becoming. My stomach looks very thin. I can sort of see my rib cage. I feel very strange, often, in terms of my body's compostition. My pants are becoming looser and looser. I can feel my joints.Okay, so what's wrong with me, and how do I fix it? Other things you might need to know: for the last 2 months, I took Immodium AD 3 days a week as either a precautionary measure or because I had some D or loose bowel. This last week, I haven't taken any. Could Immodium AD cause this weight problem? Um, what else.... I either eat small portions a lot or large ones fewer times, so I don't really do one of the other more often. I don't excersize that much, though I do literally walk about half a mile throughout my school day getting from class to class (I have a humongous High School). I do participate marginally in gym class.Also, I should mention that 6 months ago when I "fasted" for small periods, I began being intrigued by losing weight, how it makes me looks, etc. I did not intend to lose a lot weight by "fasting", I only wanted to be able to survive marching band and the other stuff I had to do. I was very emotionally traumatized at this time by my IBS. Now, I'm not in band anymore, and I generally do much less things, realizing that I need to take some time to figure things out with my IBS. I never really was happy that I was losing a lot of weight, only intrigued by it. Now, I absolutely am terrified by it, feel guilty I was ever intigued by it; kind of a twist. I don't want to lose anymore, not just for my health, but because I'm beginning to look very odd and I want to look normal and healthy.Thank you for reading my post, and thanks in advance for any help/advice you can give me.