my bf keeps beating around the bush

Me and my bf was supposed to hang out today .. didn’t happen. anyway he keeps going to this cookout every time I ask him where he’s at or what he’s doing he says hes going to a cookout or he’s at a cookout he was at this cook out for like the whole day yesterday. Everytime I asked who’s cook out he ignored the question or responded like this.. like Ok , when you ask someone who usually you say something like “this girl I know family” or “my neighbors” idk why he has to say I knew them before u. He usually responds like that when he knows I won’t like his answer . For example if he said it’s a girls cookout I’d be like why are you going to a girl idk cookout because you wouldn’t want me going a guys cookout you don’t know so I feel like he’s kind of being suspicious.. am I thinking too much about it ? How would you respond?

We’re 19 & been together 8 months.