Headache for 3 years straight everyday..?

I been suffering with headaches for 3 years straight every day all day... I finally saw a neurologist and he did a MRI, CT and an xray of my head and all came back negative and clear. He has done neck checks and finally put it down to Chronic Tension type headaches. He wants to give me something called "Botox" but Im not very sure it will work, isnt that only for beauty purposes.. He is very certain I will feel A LOT better as a lot of his patients have.

At first I thought it was my vision and my eyes because the pain was around my eyes and forhead and on both sides of my head. It seems to get worse when touching the parts of my head that hurt....

However I got multiple eye test done and only showed +0.25 in my left eye and all the docs have told me you have perfect vision and there is no problem with your eyes.. Please help me. They claim that tension headaches can cause pain when using your eyes as well. Will botox really help? I am 22.