Inn i blocked her over this
Last year I was having a heated discussion with my mother about something, I dont remember what, while holding my phone. When I looked down on my phone after a while I realized I had accidently opened the chat window in Faceboob Messenger for an old classmate I havent talked to in years, and called her twice. I immadiately panicked and therefore blocked her. I have no idea if the calls went through but I seriously hope not.
Unblock and just say that you butt dialed. Plus is it that disastrous of a mistake.
People who recognize me from highschool are the worst though because I have to shuffle through my memory to even remember their face.