I've started to feel really awful about myself

I'm 5 feet tall and 7 stone (98 pounds) and I feel awful about how I've been eating. I eat a healthy dinner usually but whenever I eat anything except fruit, I feel ashamed and angry with myself for it. It's not even dinner yet and I've already eaten 100 calories over what I should be eating. It makes me feel unwanted and I just want to disappear.