Can it be diabetes?no appetite but when i do eat a little i feel like vomiting headaches nausiate and loss 5 lbs in 1 week. not sexually active im 17

Unlikely: Diabetes at 17 is possibly, though definitely not first on the list. Nausea and vomiting most likely due to gastroenteritis, or a viral infection. A week is a long time to have this though. You may want to see your doctor in order that he/she can evaluate you and perform some tests, perform physical exam, take a medical history. Good luck!

Get a checkup: If it is diabetes, it would need to be pretty out of control to cause those symptoms. Get a check up. No matter what, it is not normal for a 17 year old to go around feeling that way.