teenage son complaining of headaches

my 14 year old son got a bad headache yesterday which he said came on very quickly. he then started to feel faint and nauseous. he has been in bed since, is feeling cold and has lost his appetite. he says the headache is constant and he feels like nothing tastes right hence his lack of appetite. could anyone suggest any causes or treatments for him. he is also still feeling nauseous and says that if he tries to stand up he feels faint immediately. I am trying to get him to eat something as I feel the dizziness is from not eating.

Could be a virus. Does he have a raised temperature? Check for a rash and if he becomes sensitive to light or develops a rash, straight to hospital. 

If if not a virus could be migraine. I get a metallic taste in my mouth with a migraine and nausea us a common symptom. 

Reading your list again, I think if he feels cold it's most likely a virus.

treat the symptoms, keep warm, drink plenty of fluids and doctor if he doesn't puck up in 2 or 3 days. If at any time he deteriorates, develops a rash, straight to A&E.

thank you so much for your response. he doesn't have a temperature but goes from feeling hot to cold. he doesn't have a rash but he does have what look like small scratches on his back that he has had from a while back. he can't understand where they came from but they're itchy. he did get a very strange rash on his face before Xmas. the doctor found it to be a strange rash that she had never seen before. he went through a course of cortisol cream and had blood test done that came back clear. the rash cleared but if he misses putting cream on for a few days it starts to return!.

I don't think a rash as far back as Xmas could be anything to do with headaches now. I was thinking more along the lines of meningitis developing. It's VERY unlikely but just something to be aware of. I was hospitalised years ago on holiday in France as I had all the symptoms of meningitis. It wasn't, it was just a really nasty virus that lasted over 2 weeks.

If your sons no better in a couple of days it's worth seeing the GP.

i think we always worry more about our kids than ourselves.