I am 27 year old female. My last period was on 21st june and ended on 26th june. I had foreplay with a guy where I was on top just rubbing my clit to his penis. He was already ejaculated by then. He wore underwear and shorts (dry shorts used for running) and I was naked. I don't know whether his semen has touched my clit or not. Now, I am having 7 day delay in periods and pregnancy test was negative. I have regular periods cycle of 28 days can I still be pregnant.