Advice needed !!

Alright y’all , this might be a little long , but I don’t really have anyone else to talk to about it . Me and my boyfriend of almost 3 years took a 4 day break . 4 DAYS ! When we got back together , I went through his phone and found a girl that was snap chatting him and he didn’t think to tell me about it ( blowing his phone up with snapchats and you forgot to tell your girlfriend , alright 🙄) . I confronted him , and he says ever sense we have been back together he hasn’t answered . Let me give you a little back story about the girl ... she goes to a mutual place we go to in the summer , one time I didn’t go , and she “ randomly “ friend requested him , or so he says . He never accepted it , untilllll we just took a break . He says they only talked about the place we go to . My question is , am I not looking into it enough , or am I looking into it too much ? I sent her a friend request and she accepted, but I don’t want to message her and act crazy 😏