Pregnant?

So me and my bf had protected sex. He took the condom off for like 30 secs ans out it back on. He was no where near close to finishing. He never did. Anyways I took a Plan B. Got my period the next week like I was supposed to. I missed my next period like the one I was supposed to get next. 17 days late. I really doubt I am pregnant but I’m going to take a test Wednesday. I’m only 18. I pray to god I am not. Give me advice, please.