Not that I'm a doctor or anything, I'd be more tempted to say the bleeding is from tearing and irritating the esophagus. I've gotten sick with food poisoning and ended up vomiting blood. It had nothing to do with medication, since I wasn't on anything.

Kylie, seek out a therapist who specializes in eating disorders. A good friend of mine was extremely anorectic and bulimic, and she was finally able to overcome it with an understanding counselor.