Hey would really appreciate someone's help as i'm going out of my mind with worry. About a month ago I was messing around with my boyfriend and tried having sex, I may have touched his erect penis for a brief moment but after that he put a condom on, as i've only done it once before we couldnt get his penis into me properly and as we were sort of time we gave up so he never ejaculted fully. I'm now a week late with my period and have had tender breasts for about 4 days, as I usually get this with pms it's not been so much of a worry but i've never noticed it go on for so long, i've also been experiencing period like pains for a few days and nothing seems to be starting. I've tried two pregnancy tests 4 days apart from each other and they both came out negative. I'm just wondering why my periods so late, is it possible that yeast infections can delay periods? Please help someone.