Stomach twitch = HIV now? Thats a new one to me. Dont woprry about the twitch, it has nothing to do with HIV.
Go ahead and get tested at 6 weeks and then 13 weeks for a final test.
It sound like and stomach problem caused by stress and anxiety, unprotected receptive anal sex does place you at high risk, so testing is warranted, test at 6 weeks for a 95% accurate result and then at 3 motnhs for conclusive.
Good luck
Forgot to mention this wiggle jiggle thing in my center stomach area happens sporadically. Never know when it's going to occur and it does not happen immediately after eating or drinking anything. My stomach doesn't hurt and no diaerrea at all. It's probably nervs or anxiety is my guess. I won't be doing that no more.