Night sweats could also be a side effect of medications. There are certain meds that do that to me. I have this often, or the extreme opposite...freezing and can't get warm.
I have IBS. First, I had endometriosis and had my uterus out. I felt better for a while and then the symptoms started to reemerge. Went to GI, did all of those exciting labs, CT scan, exam, sono, etc. Then she put me on the FODMAPS diet. I really did not like what my GI had to say, so I ignored her recommendations for a while, but finally figured out that if I followed the diet, I felt loads better. I try to be a good girl and follow it about 95%. That ain't so bad. Its kind of nice to have SOMETHING that I can treat without a medication.