Do I need plan b?

I seem to have a lot of silly questions but this is the best way for me to get them answered haha. Anyway, so I had sex last night and we were safe by using a condom. I just have the fear that the comdom wasn't enough. Every time I've had sex I took plan b even tho I used a condom every time. Should I get plan b or not? I don't know if I'm over thinking this or not. Also, my period ended on the 12 this month idk if that makes a difference or not. But please help! Thanks ladies!