My boyfriend ejaculated inside of me last night, because the condom broke and my period started this morning. Can I still get pregnant? What are the chances?

Chances are not very high, but obviously any time you have sex without protection you're risking it.

More than likely you aren't pregnant. You would typically ovulate 12-14 days before your period starts, and since you started your period today I would say you aren't pregnant. If you miss your next period take a test, but it's highly doubtful that you would.