Hmm It might be the flu . You should rest, drink fluids and take it easy.
I feel sick I want to vomit. Also loss of appetite, a bit of a headache and mild fever - what could it be?
Sounds like the stomach flu / stomach virus
Sound like you have a stomach virus. The nausea and fever is due to the virus and the the headache you are receiving are due to the lack of appetite. I recommend. Tamma Flu medicine, powerade , soft foods, Call your doctor for medical advice, Concerning tamma flu just in case there are any medication that you are currently taking or any medical problem you might have - I strongly recommend making an appointment.