cd 50 no af PLS HELP

hello everyone before my previous period started, my boyfriend and i had oral sex in which his tip (might have had pre cum) might have touched my outer vaginal area for 5 seconds. i got one period 2 days after that which was normal and some mid cycle spotting around cd 14. now im on cd 50 and i have no sign of a period except for some swollen boobs (that i get before a period) a few days ago. but now my breasts have gone back to normal size like after every period but i have had no af. do you think i could be pregnant? i’m so confused here. also i’ve been under a lot of stress since i have a high pressure exam at the end of this month so idk if that could be a factor too. please help a young girl out! i’m really anxious as it is :(