Pregnancy Inquiry. Through pills now?

I had oral sex during the month of may. There was no sexual intercourse but i doubt there was some pre ejaculation near vagina. My periods are due since two months though my periods have always been irregular and get delayed for few months. I was also administered medicine to stable my menstrual cycle. Previously i consulted a gynae and she said symptoms were due to heavy exercises you did.I had some symptoms like light bleeding, swelled ankle for two days and yesterday i vomitted early in the morning. In past two months i have done 4-5 times urine pregnancy test at different intervals, everytime it was negative. I unmarried and is a little tensed now?? Can the urine test be false for 4-5 times?? What should i do to confirm? And can i go for MTP through pills now??