Hi, I May Have Recently Been Exposed To HIV By

Hi, I may have recently been exposed to HIV by grinding my soft penis against another man's anus on New Years. I have started having small fever (99.2 degrees), gas, and constipation. It is possible the tip of my penis slipped inside him, but I don't think I did and it wouldn't have been any longer than 5 seconds if I did. What are the chances I have and am reacting to the virus?