Anxiously waiting...Advice greatly appreciated...I seriously anxious about finding out if im pregnat

I Would be so greatful for advice...Im currently on cycle day 23...10 days after ovulation...my period is due in 5 days...on May 13th 2012....i did have unprotected sex during my ovulation days but we finished with anal sex however i know for a fact a good about of semen(sperm)ended up in my vagina. Now I know you cant get pregnant from anal sex but i was wondering there is a chance i could get pregnant with semen getting into my vagina. Ive had a tiny bit of link pink spotting yesterday(9 days after ovulation) & a lil bit of brown discharge today(10 days after ovulation but it stopped so I took a preg test today think maybe it cld be implantation bleeding but i was negative. I was wondering if its possible it could just be to soon to show a positive on a preg test today if my period isnt due for another 5 days. THANKS FOR YOU ADVICE. Anxiously Waiting