My risk was having another man slide his penis between my buttox with no penetration but he rubbed his penis aginst my anus breifly. I did the same to him and accidentally penetrated for one second if that and it went in very slightly. My doctor said there was no real risk becuase there would be trauma needed. Should i be concerned about hiv??
The risk for infection through anal-genital contact is primarily associated to receptive and insertive intercourse, not grinding. If your penis penetrated for one second, it is difficult to say that that qualifies as insertive sex or represents any significant risk for infection.
What really determines the likelihood for infection is if you actually came into contact with HIV infected fluids (blood or semen coming into contact with your mucous membranes; during insertive anal sex, HIV would be transmitted to the insertive partner through contact with blood). Only you can determine the likelihood of that, but again, the risk seems quite low.