Please get Ozzy referred to a specialist to find out exactly what's going on and what can be done.
I haven't posted this before because I didn't want to scare you, but many years ago I lost my lovely 10 year old Cocker, Sam, due to damaged discs in his neck. His pain was intense and it was before surgery techniques were as advanced as they are now. It broke my heart.
Please get Ozzy back to the vet. He needs a proper diagnosis and adequate pain relief in the meantime.