Hello everyone!

Just came on here for some insight!!

My boyfriend and I (17 nearly 18) had sex twice in my current cycle- both times with a condom. After we had finished both times I made sure to test to see if the condom had any tears or anything which it did not. I am now in day 49 of my cycle, usually 30 days, with no sign of my period. I have taken two test, one this week and one the week before- both negative. Other factors that I think could explain the missed period is the fact I got off the pill 3 cycles ago- all though I have been fairly regular until this point. My cycle was really irregular before so perhaps it is just adjusting to how it was pre- pill??? Additionally I have also used antibiotics this cycle and have been under stress with exams. If someone could please give me some advice or if they think my chance of pregnancy is high? Thank you