Help!!

So two days ago bf and I had sex without a condom (I am on birth control and take it regularly at the same time everyday) and he came in me for the first time. It was also the first day of my period, so I had some light bleeding. I know the chances of getting pregnant on birth control are slim and it’s like a 1% chance of getting pregnant while on your period, but I keep freaking out. Should I take plan b? I am worried it will mess up my cycle. I’ve talked to a bunch of friends and have done some serious google searching, and they all say I probably am not pregnant. Am I freaking out about nothing? What are my chances of getting pregnant? Help!!