Boyfriend (M 22) is following girls why doing a study abroad

My boyfriend (22) and I (23) have been long distance for almost 5 years, so we’re not strangers to this. After the troubles of navigating a LDR, we’ve been at a point for a couple years now where we’ve worked out most issues and are chilling. However, he comes from an extremely wealthy family and travels almost monthly. He recently went to go on a study abroad in Japan for 9 days. This has been difficult for me, as I’m recently graduated and have a job lined up that starts after summer. So I’m bored, while he’s having all of these experiences. He made a comment, “all the girls said I have a good face card” and was essentially bragging about all the other students they met up with in the country thought he was hot. Then, as I’m on edge and had a feeling, I checked his instagram and see he’s mutuals with over ten girls he met there.
I barely get to talk to him due to the time difference and between that and the comments he’s making I’m feeling very lonley and anxiety ridden. I know he wouldn’t cheat but I don’t understand why he needs to get girls instagrams and being so much farther away and barely communicating is making this whole experience hard for me. He’s also planning on doing a months long one in the future. I don’t know, am I being extra for being upset/ stressed over this? I want him to have a nice experience, but I don’t appreciate the vibes I’m getting.