Just double checking!!

So I am 1-2 days away from my period. I see some spotting and bright red blood on toilet paper/tampon when I check and have all my normal PMS symptoms of sore boobs/bloating/etc. Last night I knew I wasn’t ovulating or anything so my fiancé ejaculated inside of me for the very first time. We both agreed until we are ready for kids that was a one time thing. We usually always use condoms or withdrawal if I am not in my fertile window. I couldn’t have gotten pregnant from last night right?