What could be the reason for my headache?

Hi, I am a headache patient from last 3 years, am 33 years male. 3 years back I used to get very often and always I used to feel headache at my back side of my head. So doctor asked to do MRI for brain, pituitary gland function and neck, my MRI was fine for all three, then doctor asked to test blood, in blood tested it was found that my thyroid levels were little high. So doctor found thyroid was due to Grave disease and treated with Radio IOdine(ROI 10mci), now I have become hypothyroid and taking supplement (thyronorm), and now my thyroid levels are proper. But my headache still hurting so doctor also checked the BP and ECG, both are normal. but still I have the headache so doctor suspected it might be migraine and started treatment with migraine, they asked to take sibelium 10 mg for 3 months (https://www.lybrate.com/medicine/sibelium-10-mg-tablet).

So I am confused what could be the reason for my headache, I am thinking its not migraine because my symptoms are like below 1.Still I feel headache at backside of my head whenever I stand-up or stretch my body 2.I feel little giddiness when I took stairs or suddenly rotate my head from resting position 3.Morning its very difficulty to get up, my head feels like full weight 4.And I never felt my head is free like I used to fell three years before 5.I feel numbness in hand (if I lift my hand and put it on wall for few minitus) and leg and foot muscles when I sat on the floor with closed legs. So I am confused, is it due to thyroid or really have some problem.