I've been to the doctor who has told me that I have Sinusitis. I've had this before a few years ago so thought that this could be it again. He told me to drink more water! How can that be possible, I drink heaps now, but apparently when you have this, at night time you breath through your mouth which loses 20% more fluid making you dehydrated causing the headaches.
So this also explains the cracked dry sore lips that feel like footballs. Drink more water, if it was that simple when you are already drinking over 2 litres a day.