my boyfriend won't let me in.

okay. so this started last night when my boyfriend & I were talking about being friends w exes. I'm still friends w an ex (we dated for a couple months, but we've been friends for 6 years and that's why we've remained friends) & he's still friends w an ex (he only dated her for a couple months also). I'm cool w it, he's cool w it, whatever. I wanted to see what she looked like, right? so I saw her on Instagram & I followed her. didn't really think anything of it, I wasn't trying to be malicious or anything, I really just didn't think anything of it. so this morning he asked why I added her & said he knew because she messaged him & said, "you know your girlfriend thinks something is going on when she adds you on social media." & it upset him that I added her and I didn't understand why. he even said "you don't see me adding *my ex boyfriend's name* on anything." & when he said that I just kinda thought.. but I wouldn't care if you were? I would love if he were friends w my friends. is this weird?