Bf is mad I posted bathing suit pic

Ok so my bf and I r teens. We’ve been together a year and a half. I recently became a life guard and I posted a pic of me in a full piece bathing suit on my Snapchat. My bf is rlly mad about it cause he doesn’t like that I showed my body and he thinks I’m trying to get guys and he now doesn’t wanna talk. I posted it cause I felt confident at the time and wanted to show off my life guarding bathing suit. Am I in the wrong? Or is he overreacting? What should I do.