Neck stiffness, pressure in head

Hi

im 9 weeks post radiotherapy to palate and neck. Had neck dissection December. 
is it usual to be so stiff!! My neck hurts pretty much all the time on any movement and i can feel it crunching when i move my neck and head. My head feels full like a pressure cooker !! Im deaf with terribly loud tinnitus in one ear. Its so debilitating. My head feel likes like it’s throbbing and doesn’t help because i can hear my heart bear in my ear. Is this usual and will it get better? So tired still and feel weak and wobbly. I feel like im getting worse not better. Anyone else experience this? 
thanks x