Lower left side hurted for a bit

My period is in 9 days and ive been having unprotected sex and my boyfriend tells me he doesnt know if he cummed or not but yet 4 minutes later he cums. That may sound confusing idk but thats what he says, and right now my lower left side started hurting which i dont know why i never really experience this idk if it has to do with water but i drink plenty of it it was like a minute then it went away, just let me know. Yes i want to be pregnant:) hope you aint being sarcastic with me :) but i dont want questions asked to me im asking yall a question 🤦🏻‍♀️