I have a lot of pimples in my hair they hurt really bad and are progressively getting worse. I have changed shampoos' I have stopped wearing a hat (As much) and these things keep coming back. Any ideas on how to prevent and what this is? Thank you

It's probably folliculitis, inflammation of the hair follicles, the little bulb that surrounds the base of a hair under the skin. It's often either a staph infection (bacterial) or fungus. But on the scalp, it's more often staph. That means you have to see a doctor for either antibiotics or anti-fungal treatment. You can try dousing your hair with anti-bacterial hand soap, but it might not be enough. Rinse well whatever shampoo or soap you use, always, and let air circulate to your scalp every day. I don't know what kind of hats you were wearing or how many hours a day, but a too tight hat isn't good, or one that is never cleaned.