My girlfriend is in pain after the first time?

This post is a bit embarrassing for me

So my girlfriend and I wanted to take it a step further and have sex. We used contraception, a condom, and used it properly. After the first time, she said that evening she had abdominal pain and a terrible stomach ache, and she also felt nauseous.

Now I'm a little worried that she's pregnant because she said so, and I'm worried that I'll get stress from my parents and so on.

Did anyone help

Thanks for the answer if someone helps me