I want to call out my friends wedding invitation
Why? Were you not invited or something?
I found out about the wedding invitation on social media
I'm sure if they didn't send you an invitation they have a good reason for not doing so. Reach out to them and find out what that is, rather than questioning their wedding plans. Hopefully you guys can work this out!
I'm allowed to send them a message, right?
I am sorry you didn't get invited but I think it would be ok to ask about it. Sometimes invitations get lost in the mail and you have no way of knowing about it. If she didn't send you one just try to be calm and understanding.