Am I wrong?

This guy that I’ve been “dating”to for about 2 months (we are basically together but not official) always has this one girl commenting on his photos saying like “best friend❤️” like EVERY PICTURE ...I understand that i have no right to tell him who he can and can’t talk to. I’m just a bit worried that they are more than friends. I might just be trippin too hard bc we aren’t officially together but he said he’s mine and I’m his...am I wrong for feeling this way? I’ve never told him how I felt about this bc I don’t want to make a big deal out of her being friends with him.

Edit: Don’t worry about it anymore I don’t think we are going to work out even though I wanted us to...