Am I being too jealous??

So my boyfriend and I hooked up in mid September and have been dating pretty much since (I’m 17 he’s 19), I lost my virginity to him but he lost his to one of his friends who he had a thing with over the summer about a month prior. My problem is that they still talk, now I know they were friends prior to them Hooking up but it bothers me that he still has a Snapchat streak with her as I cut off all communications with guys I had been seeing over the summer out of respect for him. However she did move out of town so I know they aren’t doing anything but I’m scared he still has a thing for her :( I hate the idea of being a crazy girlfriend and this has been driving me nuts can someone please help 😫