Idk if its okay to be a little annoyed

Okay so I have this one friend, who has introduced me to a bunch of her friends and everytime we hang out together, she and the others say we are having so much fun etc, but she is never the one who asks me to join them unless I ask her what she is doing and happens to have made plans with the boys I mentioned earlier. We've been friends for many years now btw, so the question is, am I allowed to be a little annoyed or am I just overreacting? Also, my period will start in a couple of days, so that might explain why I'm feeling like this, but anyway. 😅