Most Helpful Girl
STOP DROP AND ROLL.
I know it's hard, because I've been in the exact same scenario (and did something very similar).. The key to this is to measure how urgently you want to message her. The more you want to message her, the more important it is to make sure that you do NOT message her.
Do not send anything. Do not send apologies, because they make it worse. Do not say a word. Give it silence. Unfortunately, you're going to have to move on now.
That is the only chance you'll have at maybe possibly getting her back, but it's slim... The best thing for your chances now is to start dating someone else, and if she comes back to you, great. If not, then you'll know not to do this next ime.
Sorry buddy, I know it sucks to be there :P