No, I haven't been tested for food allergies, but I wouldn't be surprised if that's not a problem because when I was younger I had many allergies and had a series of shots (over 1½ years) to help with my allergies. It really helped but I'm pretty sure they didn't test me for food. They did the prick test on my back. That was way back when I was in my early 20s and now I'm 47.
Right now I'm still not sure what causes the problem other than in the past year I have had a lot of stress and my dr. said that can be a contributing factor. I have wondered about ice cream (which I love and eat a lot of) and I see people on here saying it does indeed make IBM worse. I really hate that. I've been trying to cut down on the ice cream. Now I guess I'll have to try harder.