What Causes Throbbing Headaches With Body Aches?

Hi I am 32 years old and generally fit and healthy. I flew to New Zealand from London arriving last Wednesday, I felt fine for my first couple of days but got a terrible head ache on Friday night which I still have, everytime I stand up it really throbes, I am also aching all over my body. I thought that it was maybe jet lag but I am worried that it has lasted for 3 days and is not really getting any better... Do you think I should see a doctor or give it a few more days. I feel fine otherwise, no sickness or cold symptoms