I’m in the middle of a eating battle

I’m not hungry any more and its kinda freaking me out because the last time this happened, when I just all of a sudden wasn’t hungry (for no reason, food just didn’t appeal to me) I lost 30lbs I went from 120 to 80 and I’m 5’6”. I dont know what’s going on and it’s starting to hurt my stomach to force feed myself. Has anyone else gone through this? How do I handle it? I’m back up to 115 and I don’t want to drop all the weight. It hurt to sit down for long periods of time for shits sake!