Hey Guys

So I have been trying to get this dino rigged ( followed the digital tutors rigging tutorial for maya) but Im getting strange problems with the neck and head in terms of rotating

https://www.youtube.com/watch?v=oHCMnxkZ26M

I made a quick video to illustrate this, the neck for some reason started rotating as you can see and the head is sort of acting like it has parkensons when moving. Any help would be great