Thank you n/m

So I'm embarrassed to share this...

I was bulimic for a year, and I didn't think it had done much damage, but this morning when I looked in the mirror due to the recent excessive bleeding of my gums, I find that my gums have receded terribly, my teeth are horrendously gray/brown in color, and that a few of them have HOLES in them. One is so bad that when you look directly at it on its front side you can see an exposed nerve.

I am under 25 and I am freaking out. What did I do? Did the acid eat the enamel away?
Can I repair my teeth through natural means?

PLEASE SAY YES!!


P.S. If anyone knows how to REGAIN MEMORY FUNCTION after a concussion, that would be awesome. I can't even remember what I do the first half of my mornings - much less what I did yesterday!