Is your neck getting stiff at night or sitting in one position for a long time? This will give me a migraine eventually if I don't get it worked out with my theracane. I would mention it to your primary care Dr. It might or might not be due to the injections but something else.
Could be Uveitis or Iritis coming on.
I had no idea Voltaren gel could work on your headache. I'm all over that. Have lot's of the gel.
Shane, I would just have it looked into a little more to be safe. Can't hurt.