I Got A Terrible Headache In Which I've Had For

I got a terrible headache in which I've had for days, sore throght and a runny nose. Everyone keeps telling me it's just a cold but I'm not sure. I've had colds before but never like this. I've got a constant headache and my eyes are constantly watering. Never in both eyes at the same time. I understand that a runny nose and sore throght are typically symptoms of a cold but I've never had a headache anywhere near this bad. What could it be?