He talks to my friends still, is that odd?

I've had this weird gut feeling for awhile that he's gonna say something to me sometime soon and it's been making me kinda anxious. He started talking to my friends maybe a month-ish after we broke up (while he did talk to and know my friends he never had a super close or solid bond with them, he was just kinda "ur friends boyfriend" to my friends)

After awhile of knowing this (with my friends telling me about it) I did get kinda anxious and wasn't sure why since I genuinely didn't rlly care. Even more so when my friends admitted they didn't rlly wanna be friends with him they just wanna be nice

With the gut feeling though I think I know why I was so anxious and why my gut is screaming at me, he's still talking to them. Is that odd in anyway for your ex to keep contact with your friends? Or am I just being a paranoid/anxious freak?