Don't beat yourself up about the drinking...maybe you needed to do that at the time, just trying to take the edge off all the stress. As M said, we've all done it. Go ahead and cry, then drink lots of water today, find some B vitamins somewhere if you can...and know that this cruddy feeling WILL pass and you will feel better before long.
Also, in that state I find that McDonald's french fries and a vanilla shake make me feel better! Don't ask me why! Couldn't hurt. :P
