Hrm.. well if you do tell her.. then she may want to get it as well. "Well ,if mom got it, why can't I?". On the other hand she's probably going to be happy that you're happy, and know what she's going through. I say if you plan on getting it for her too; tell her. If not; don't. ^^
A "crybaby" is definitely not the word you should be using. Surgery is a scary thing, but you went through it once. & are strong enough to get another surgery done. You should give yourself an attagirl. I have panic attacks too. So just listen some relaxing music, breath slowly, and think of the brighter things that could happen when they put that mask on. Good luck! ^^