Help me please!!!

Hi everyone, so a few days ago I wrote on eve talking about how I took Plan B after I gave my boyfriend a handjob then touched myself and how I was getting worried that I had such a short period (which isn’t normal for me). My anxiety got the best of me and I started to freak myself out so much over this. Even though I know there is nooo way I’m pregnant due to my circumstances does anyone have any advice on how to calm my nerves down and have me stop worrying about it so much?