Need help not being paranoid...

Hey there, super new to this app, but a friend told me about it because I get so paranoid about sex. So I need help...

So last night, I slept with a guy. I’m on the pill and he wore a condom. However, before anything happened I took a prescribed ibuprofen, which I don’t even know if that does anything. Second at some point the condom came off, and we don’t know when. It could have been when we were done, but he didn’t pull out.

I took a plan b pretty much 30min after everything was said and done because I was so paranoid. So 1, please help me feel better because I do not want to be pregnant and 2 what can I expect from plan b since I’ve never taken it.

Also my period is extremely abnormal, like has been my entire life so it’s hard for me to rely on that.