Am i wrong in this situation?

Everytime there is a new event,or something happening in town,my friends always invite me and expect me to come with them even if i cant or my parents dont allow me(in this situation one of my friends get mad at me).Recently me and that friend went to a concert(there are 3 of us in this friend group),other friend went with her other friends and the friend A,that i went with,didnt get mad at her or anything,but soon after both of them invited me to a concert and i said i already said ill go with my cousins(friend A never want to go with my cousins when i invite her with us).She got mad at me,and insisted that i say no to them and to prevent anything i didnt go with anyone.I am so mad at myself for not setting boundaries but everytime i try,its turned back on me.What should i do?