Unsure if i could be pregnant

I had sex for the first time 2 days ago. I am constantly stressing because even though we used a condom and i am certain it didn’t break, my stomach has been cramping quite a lot and i am stressing that this could be an early sign of pregnancy. I want to get the plan b pill, but i don’t know if i am just scared for a stupid reason. I am ill at the moment as well, so that probably isn’t helping how i am feeling. Someone please tell me what to do, i feel like I’m stressing out over nothing but i cant help it 😩