Would you be worried?

I took out my nuva ring on Wednesday and later that day my bf came inside me so I took a plan b the next day and then we had sex again on Friday morning and he came inside me again. I’m supposed to start my period today but no sign of it. I feel a little crampy here and there. My bf and I have stable jobs, we don’t live together but we have been together for a little over a year and we both have one kid from our past relationship, so we’re not exactly looking to have a child but we are avoiding it that’s why I’m on birth control.