Hi, I am 20 years old. Female. I had unprotected sex with my boyfriend last March 12 for about a minute or less (note that it was also my first time to have intercourse and because it was unprotected, I asked him to stop before things could get worse). My expected period date was March 31, and it is April 18 where I am today and I still haven't gotten my period. But even before that one time we had intercourse, I was staying up late, eating and sleeping less because of school work, and up to this day, I only eat once a day. I have not taken a pregnancy test yet but I was wondering if it's possible that I could be pregnant even if said intercourse only lasted for a minute and also if I'm constantly losing weight? Also recently, I have been feeling irritable (I wanted to ask if weather could play a part in irritability and fatigue because in my country we've been having 40 degree weathers lately) and today I got brown cottage cheese like discharge. Last week I got a bruise out of nowhere and usually it's a sign that my period is coming. Also I have been experiencing some severe back pain. So far I have not experienced any sicknesses whatsoever. Thank you so much for your time. Your help would mean so much to me.