How much cereal did you eat?!
That aside, I'm gonna echo Jordan here. Please, please, please (and this goes for you as well, Anon 2) get some help. Doesn't have to be a doctor, doesn't have to be a counsellor. Could be a flatmate, an old friend, someone you meet in a club (though I'd suggest getting to know them a bit better before telling them all your issues!). From what you're saying, I think it's a lot more than Bulimia.
Please don't fast tomorrow - Set yourself an aim, like eating one banana before say, 11, then between 11 and 3 eating a couple of pieces of toast, then by 7 having eaten a yoghurt or something. Did you know you lose more weight when you eat healthily and exercise regularly?
ETA - Anon 2, you're spot on the money there. Anon 1 has a very complex relationship with food that none of us can truly help with, but a mental health care professional can.