Loosing it

So I'm a teen and I just recently lost my virginty. It was awful and I regret it so much. But what I regret the most is that I did not use any form of contraception. But he never did cum inside of me. But still I've heard that precum can still get you pregnant. I'm so scared and I can't tell my mom. And I do not start my period until usually around the 15th. What should I do? Should I wait until my period comes? Should I even be worried?