What Causes Excessive Hunger Along With Feeling Of Nausea?

I can usually eat breakfast but by around 11 or so i get really hungry for only a short period but then it turns into severe nausea that makes me stay near a trash can. I can usually beat small stuff like cheese its but only every couple minutes. Then at dinner im starving but when i try to eat i feel like im going to get really sick again. Then i end up eating nothing. There is also always a lump in my throat and my stomach is bloated. The nausea has gotten so bad its almost constant now. What could it be?