Missed Period

Okay so I’m getting nervous but 2 weeks ago I had shower sex with my boyfriend, and well it wasn’t working that well so we stopped and he took off his condom so I finished him with a HJ. Now it’s been two weeks since that day and I’m 3 days late from my period. It was suppose to start the 20th. The only thing different is that my nipples hurt. Could I be pregnant? I’m really nervous knowing I’m only 17.