I'll try to help. But I'm going to be brief, since essentially the same questions have been asked and answered hundreds of times on this forum.
Symptoms never are useful indicators of new HIV infections, because other things, much more common than HIV, cause the same symptoms. A negative antibody test amore than 5-6 weeks after exposure always is more accurate than symptoms. Blood tests tell the truth, and symptoms usually do not. And your symptoms don't sound like HIV anyway. But even if they did, your test results indicate that something else was the cause.
So the direct answers are: 1) No, your symptoms are not due to HIV. 2) Except in unusual (very high risk) situations, HIV antibody tests are conclusive after 7 weeks, regardless of symptoms.
3) Should you retest? Probably no, but the nature of your "high risk" exposure make a difference. If in doubt, see a health care provider then follow his or her advice. Even if s/he recommends a 3 month test, you can be certain the result also will be negative.
Good luck-- HHH, MD