No data was given if any damage was done to the brain tissue and where the location of the damaged tissue is. The anterior part of the brain controls the attitude, the mood and the emotions.
You might want to ask your doctors if the anterior part of the brain was irreversibly damaged when you had your head injured.
If there was no irreversible damage, then you might be experiencing bulimia combined with obsessive-compulsive disorder. An observation and adequate medication treatment controlled by psychiatrist is recommended. You might want to visit a psychotherapist, too.