Well today I am feeling better. I am able to do complete neck circle in both directions without any pain or sticking points. For me the sticking points were looking all the way down, up and down and to the left. I am able to do all 3 today comfortably.  

I have an appointment set up with the ART specialist tomorrow that I will be keeping just to be on the safe side. Have you looked to see if your have an ART in your area? The way I found mine was asking around the local boxes and see who they recommended. 

As far as the tennis ball goes I think you need something better. Get yourself a set of lacrose balls and a set of the Yoga tune up balls. I have both and use them everyday on something different. The lacrose balls work wonders on your achiellis tendon and loosening up tacked down skin. The Yoga Tune up balls work really well on the more tendor areas ( ankles, Anterior tib… bonier areas that a lacrose ball would hurt. ) It will be a great $20 spent, I promise you that.