Marriage

I think I might be overreacting but this girl manager at my husbands workplace recently he has talked about her and he told me he has texted her just about work and read me the messages which I didn't ask. But recently I found out he's back on instagram and has followed her on there. I know he talks to her at work,but now idk if there is something going on? It makes me nervous because that's how we met was through work and become close friends.