Help !

So me and my bf broke up and I hooked up with another guy, he pulled out and it was one time. While before we broke up my bf came in me every time we had sex (3-4 times a week) and then when we got back together we continued. I found out I was pregnant a few weeks ago, could it be the other guys or is there more of a chance of it being my bfs.

Sorry if this is confusing !