Your concern is genuine. Your picture is suggestive of some fungal infection in your intestinal tract which may be alongwith other serious infections like even HIV. Well it is always better to get tested for HIV after High Risk Sexual Bevaiour. The tests which identify the antibodies produced by the body against HIV require longer time to become positive - may be from 6 weeks up to 6 months due to the window period. However, Nucleic Acid Amplification Tests that you have mentioned have very short window period and can detect the infection much earlier and reliably. There are various types of Nucleic Acid Amplification Tests. All the non-HIV practitioners may not know them by the name Nucleic Acid Amplification Test. Polymerised Chain Reaction (PCR) is one of them and almost every one now a days know about it. So better mention that to the laboratory. Even if they are not doing it, they can direct you to the peoper laboratory of centre. However, HIV infection is very unlikely to give rise to any such diseases so early. Still anal intercourse carries a great risk of HIV transmission. Therefore it is a great idea to get the test done for HIV. Now coming to your symptoms, I would advise you to get stools examintation done to find out the presence of any parasitic infection or fungal infection. Proper antifungal treatment from your doctor will take care of such infection. Any other parasite found can be treated by the related treatment. If your partner is tracable, please get his HIV test and penile examination also done which may give some clue of the infection and the required treatment. And few more advices: 1. Please avoid any premascous sex. 2. Any sex when not performed for the sake of impregnating the woman should be performed with the use of conom to avoid nasty infections including HIV. Hope you are convinced.