Should I be worried?

my boyfriend and i have been having some slight issues... then today, he tells me that he has to tell me something. it took about an hour of me asking for him to finally tell me.

he said that he had met these girls, his "neighbors granddaughters" in his front yard and they asked him for his snapchat (he said yes) and asked him to go ice skating (he said yes) ..... he told me and i just said that, i cant make him not go bc im not his mom, and he's been repeatedly saying that he's surprised i'm okay with it.. i'm just kinda like "yeah..." and im not okay with it but i cant stop him.