Do I have a right to be mad?

Okay so my bf of 4 years just moved to a new city for 6 month internship. I am away at school so we are long distance and it just works. Well I am logged onto his insta as one of my accounts...he gave me full permission to posts photos from my camera of his car and stuff on his insta. He is well aware I am still logged in and doesn’t care. He posted a story today when running and legit this girl messaged and said he should run there at sunset. I was like okay kinda weird she messaged him that but whatever I’m not the jealous type. Legit my bf goes I will take you up on that offer and asked her when she wants to go. I am fine with him having female friends but I legit have begged him for 4 frigin years to workout and go running with me. Today is the first day all year he has exercised. I pissed that he would so easily do something like this when I have begged for years so i wouldn’t have to run alone. Do I have a right to be mad? Would you?