Yesterday my boyfriend told me that his friend was having a bonfire. He wasn't sure if he was going or not, but he said I was more than welcome to join him if he went. He told me he'd let me know. 
I sent him messages at 8 and 9:30 asking what was going on. Finally 10:30 he messaged and said he had fallen asleep however now he was leaving his house to go to the bar with a different friend. I asked what about the bonfire and he said "it's too cold and I'd rather go out anyway". The bar is 45 min away from my house and he told me his brother and sis in law were at the bar and it was best if I just stay home (his sis in law doesn't like me).
 I went off on him for switching things up and excluding me and he says "I don't need a babysitter every time I go out". I was angry and blew up his phone with texts cursing him out, finally calmed down and went to bed. We're supposed to talk this morning before we meet up at an event with other friends. 
Am I overreacting? Or do I have a right to be mad here? Does anyone else get mad when the plans are switched?