Please try and see a doctor, but it sounds like you have migraines. I have all the symptoms you describe. Migraines are the most common cause of headache on one side of the head.

I don't wish to scare you, but I have endured migraines for some 35 years post-injury. They did become progressively worse over the decades (I was suicidal two years ago). Imitrex has been the most effective treatment for me, but is not 100%. Maybe you could try some and see if it helps on your next attack.