Pain in the neck

Started the same workout this morning but only did 2 circuits because I jacked something up in my neck. I actually originally did it on Sunday while doing the workout but it was feeling better today until midway through my second circuit. I was doing my pull ups when I noticed it and it hurt pretty good so I bailed after 2. I have hockey tomorrow so will try again Saturday and pay real close attention to form and see if I can figure out what the deal is. I also dropped my rest time on the intervals to :50 today with no real issues, not bad when you drop :05 at a time.