Hiv Risk from unknow anal sex

hi,

am unsure if I had anal sex or not.  I had oral sex with another man and rimming with this guy but not sure if I had anal sex being an anal virgin.
There was no lube about so the only lube would have been saliva.

I was on all fours while he was rimming me and then when he stood up my hand shot back to prevent his penis entering me. When i check in the mirror the next day as much as one can there was a small bruise the size of pea by the rectum.

Question is:
A) Would i know if he tried or had anal sex with me?
B) If no cum or visable blood whats my HIV risk

[Teak]

Yes, most definitely.