It sounds like your brain has had a rough time. Have you ever had any diagnostics and work on your neck, especially your upper neck ? Neck injuries are common to 80% of concussions. They can cause head aches, dizziness, and a whole myriad of symptoms. The recent hit could have caused you to jerk you head back and aggravate a residual injury for the softball hit.

I suggest you take this recovery slow. With your history, you have a greater likelihood of prolonged symptoms that can seriously restrict your job. I think you should be seriously considering your options for your future. I'd be concerned whether you can be the reliable back up to other officers in a high stress/risk situation. The stabbing head aches are likely vaso spasms. They can go away then hit you at the worst time and completely throw you off your focus. I have them and have not found any treatment for them. Docs don't know what to do with them.

You should check out the Vitamins sticky at the top. Look at post 101 for Nov 8, 2014. It has the latest information. The injured brain has more nutritional needs that an uninjured brain.

My best to you.