I have irregular period ever since. On Feb 19th, my boyfriend and I had sexual activities. but no penetration. I am afraid that some semen came in contact with my private part. On Mar 22nd, I had a very light bleeding for 2 days, I am afraid that it is an implantation bleeding. After a week, I tested with HPT and resulted to negative. It has been 2 weeks but I still don't have my period. Is there a chance that I am pregnant?