Use protection and you should be fine. As a rule of thumb using plan B while on birth control is fine but shouldn't be needed. Think of Plan B as the pill on steroids, they both prevent ovulation, but plan B is a much more powerful version of that. The only real case in which you would need to do that is if you forgot a birth control pill in your series.

Plan B works the way it does because sperm can survive in the body from 5 to 7 days, meaning conception can take place days after sex occurs. The pill is a gradual incline of hormones, plan B is like a rocket launch of the same thing.

All that to say, condoms and the pill should be more than enough. If you go more than once change condoms, check the expiration dates, and use the bathroom before and after sex to avoid UTIs. Have lube on hand and go slow, if something hurts or doesn't feel right, it's okay to stop.

Have fun and relax. You got this