I have lost my appetite and its making me feel sick

Patient: I feel quite sick in my stomach, i am suffering from big amounts of stress at the moment. My appetite is off and on, but i cant eat normal amounts of food. Day by day i feel worse with this. I just want to know how to fix this.A week ago i was also hit by a car while riding a motorcycle. Im physically ok but that has also reduced my eating.

Symptoms: Loss of appetite, sick feeling in my stomach, Occasional headaches.