HIV is not diagnosed by symptoms. The symptoms people think are HIV related can be caused by many other things. As long as you always use a condom, you will not have a risk for HIV. Using condoms prevents HIV transmission for vaginal or anal sex. The only other way people get HIV is sharing IV drug needles with infected users. Oral sex is not a risk because saliva and air deactivate the virus. Hand jobs, touching fluids, etc. is not a risk. Therefore, your self diagnosed case of oral thrush and cotton mouth is irrelevant to HIV diagnosis.
I agree. Doctors never use (self diagnosed especially) to diagnose HIV nor do they worry about that much. Taking a test during the appropriate time is the only way to ever know. And understanding the risks is the way to prevent. The only risks are unprotected vaginal or anal sex or sharing Iv drug needles. I guess I'm being redundant to Chima's advice which is excellent.