Colds generally run over nine days, three days coming (sneezing, aches, scratchy throat), three days here, ( bunged up, headache, sore throat), and three days going (all symptoms fade).
However if your headache lasts longer or is severe, and causes pain in the face either side of the nose or above the brow, gets worse when you lean forward then it could be sinusitis.
Do lots of steam baths to prevent them, after each steam bath blow your nose GENTLY, whilst hanging your head upside down. Blow too hard and you send infected snot into your ears!
Don't eat or drink any dairy foods especially chocolate as it makes mucus worse.
Take lots of vitamin C and regular doses of paracetamol for pain, always be careful to not exceed the max dose, and Decongestant orally ( the nasal ones can make it worse).
If symptoms of Sinusitis last longer than 7 days see your GP you may need antibiotics but generally it heals well without intervention.