Condom broke 🤦🏼‍♀️🤦🏼‍♀️

Me and my bf have been together for over a year and our sex life has been great. About five months ago I got an IUD and we still use condoms. Today the condom broke and before we caught it...well ya know. This guy FREAK OUTS. I’m talking full anxiety attack, to the point the only way to calm him was to take a plan B. Any advice on how to talk someone down from this???