No appetite and can't keep food down?!

I'll try to eat but I just puke it up right away (not on purpose) and it's just out of impulse I can't keep food down and I have no cravings and hunger what is this called
And Jesus Christ people I don't do drugs or drink and I haven't had any surgery and just want to know the medical name or disease name. And I am not worried about fatty foods or calories or about if I'm skinny or not so I haven't tricked my mind into believing eating anything is bad for you and so it wants nothing