Hello Doctor, I Had Unprotected Sex With My Fiancé 2

Hello doctor, i had unprotected sex with my fiancé 2 days ago..but that didnt even happen properly since it was the first time...only half of his penis was inserted inside my vagina...he is very confident that he has not ejaculated inside..i am not sure about it..i am already a pcos patient.
I was on diane 35 for 3 months around 2 months ago..then for 1 month i got periods naturally and now my date was due on 28th September...should i go for an ipill since i am sure ? Is it safe to take ipill for a pcos patient ?
I will be highly obliged if you answer my question asap..thanking you in anticipation :-)