Your symptoms could very well be related to thyroid function (or lack of). Have you had any testing done to confirm whether or not your thyroid is working the way it should? If your weight is fluctuating, it could be that your thyroid is "sputtering" - meaning, it's producing extra amounts, then may not be producing enough.
At the very least, you need to have Free T4, Free T3 and TSH tests done. If you've never been tested for Hashimoto's, you should also do that, as well. The antibody tests you need are Thyroid Peroxidase Antibodies (TPOab) and Thyroglobulin Antibodies (TgAb).
If you can get those tests done, we can help you interpret them...