It would be a good idea to be tested again, since HIV can be undetected for several months: http://www.mayoclinic.com/health/hiv...-and-diagnosis

From what I read, if your HIV status is negative then it is unlikely you have AIDS. However, since the HIV can be undetected for a period of time, up to 3 months, then repeated testing would be a good idea.

Your GUM clinic would be glad to help with your concerns too.