Been having swelling/pressure behind eye and causes discomfort. I have had a small head cold and have had head cold b4 but nvr this. Is it a tumor?

Probably not. There are more likely diagnoses that would cause your symptoms than a tumor.
Least likely. A tumor is not likely with these symptoms. Have your doctor check your blood pressure.
Very unlikely. When you have a headache, it is important to not think of the worst scenario. Logically, one should think of the last significant health change as the source of the problem, for you it would be the "head cold", which in fact could be a minor sinus infection. That could easily explain the pressure/pain.