Confused...

Ive been with the same boyfriend now for years and I’ve been on and off using birth control. I finally stopped all together because my body just constantly rejected it. We’ve been using condoms but one night we had a quickie without one. Now, since i’ve been with the same person for years i pretty much know when he’s about to/or does cum. I felt his dick twitch inside me but he stopped for a second, kept going, and then pulled out and orgasmed. I’m wondering if it’s possible that he did cum inside me if I felt his dick twitch? I do want to take a pregnancy test because i’ve been constantly thinking about this but I also don’t know if i’m just overreacting.