husband talking to another women

My husband has this "friend" he says. They hangout with groups. She's on his snap chat. I picked up his phone and saw she snapped him a picture of her legs. I flipped. So he deleted her. Days later I then look in his texts and he was sending her "funny" memes about anal and then was like well I can't snap you back but took a picture of a snap he took and sent it to her. She's like 10 years older than him but this bothers me. He deletes his texts half the time because he says it's a work phone and work related. He says he's aloud to have friends. Am I overreacting? I'm 16 weeks pregnant. What should I do?