You gotta tell someone about this. A friend, family member, professional, someone before it gets out of hand. This stuff can kill you, and if not that, it will hurt your body. I've been trying to stay away from purging because the last couple times I have, blood comes up. And for what? To be super skinny? Everyone thinks it's gross to be that skinny anyway. I know it's hard to tell someone or try to fight it, but it's like a drug you have to put down.
A doctor can help you pinpoint the real problem in your life that's coming out as what you're dealing with, and then you can work on that instead. ED comes from a feeling of lack of control most of the time. Try to ween your way up on calories, and just eat healthy stuff. That's a much better thing to pride yourself on instead of a super low weight.