Meeting his friends ,

Yare
my boyfriend (9months (19yrs old)) introduces me to his family early in The relationship, before The month. Me and his family have been close since the first day and him with mine. However I haven't met his friends yet, his friends birthday is coming up and he says that the only other girl there is the birthday boys girlfriend and his family. That he doesn't want me to feel bad while he si with the boys, he says he also doesn't want me to think bad of him because of how stupid he gets with his friends. However I think I should know who are the people he hangs out with. I have only met one of 5, what do you think??? Should I overthink this or is it not a big deal?