Constant throbbing pain top left hand side of head. comes on during day, pain alleviated during jogging. diagnosed as tension headache by gp. tumor?

Need MRI: Brain Tumors are very rare. So, it is very unlikely that you have that. However, headaches is one of the most common presenting complaints of brain tumors and many new cases had headaches for months before anyone ordered the right test. MRI of the Brain with contrast is the test of choice. Ask your GP for this but your insurance may deny it. You will then have to appeal, but don't give up.