Please, I would advise seeing a counselor. Print off some of these online tests and give it to them if you don't feel comfortable verbalizing it.
After your body gets so comfortable with purging, before you know it your body won't hold ANYTHING down and you'll find yourself puking without your control.

I believe purging as another form of self-injury, but that's just my opinion. You're purging to replace wounds.

Keep coming back to Psych Central! You'll find LOTS of encouragement here and many people willing to chat with you when you need a distraction.