So glad to hear of your good progress! That is awesome!

The good news is that your headaches are probably related to your neck injury. The bad news is that one alignment won't permanently fix the problem. You also need to strengthen the muscles along the spine to hold the discs in place so that they don't "creep out" like you're experiencing now. Otherwise you will have to have repeated realignment over and over in order to remain pain free.

I would suggest scheduling several appointments with the physical therapist if you can. He can re-do the alignment, but also ask for exercises to help strengthen the muscles along the neck next to the discs to help hold the alignment in place. Sometimes the PT offices will have special equipment (at my office it was called a Med-X machine) that specifically trains those muscles.

Congrats on your awesome progress! Hope it continues!