sounds exactly like what I've had for almost a week - had a sore throat of epic proportions, was shivery, coughing etc - hardly able to eat for three days - just had lemsips etc and water - had aches where I didn't know I could ache, was tired with a headache to end all headaches -despite lots of the usual pills and potions for the aches and pains (especially the headache which I just couldn't shift) the penny finally dropped that I hadn't had any caffeine for over three days - checked out caffeine withdrawal symptoms on line and found one of them (for some people) was mega, mega headaches -had a cup of tea and within five minutes the headache disappeared. Just proves was a powerful thing caffeine is.