I don't know anything about your meds. Is this being cold a new thing? I started getting cold about a year ago. I went from being comfortable when the outdoor temperature reached 60 to be comfortable when the outdoor temperature hit 85. I spent nights unable to get anything done because I had to walk around the house in a huge blanket. I even had to sleep with an electric blanket... and I used to be someone who couldn't even wear socks to bed in winter!Anyway, I babble. I had all the tests you did. Based on all my other symptoms, my doctor thinks I am in perimenopause (I am only 33, but it happens). Some women get cold while others have hot flashes (actually, those have started too, about a year after the coldness started).But I also think it could be stress related, maybe even IBS-related. If you are D, you could dehydrate easily, and water helps regulate your temperature.