Thank you for the additional information.
Unfortunately without seeing her and running a few tests there is no way to know for sure what is going on.
The most common cause of a stiff neck in dogs are.
*Meningitis- Symptoms include fever, stiff neck, hyper-reactivity to touch, and reduced mobility due to stiffness.
*Ruptured or herniated disc in the neck- This is possible but we normally see limping or paralysis in the front legs or in some cases all 4 legs
*Problems in the brain such as a tumor could also be the problem in a senior dog.
I do not think this is just her being a drama queen it should like she is in pain and I would suggest getting her into a vet as soon as possible.
I would take a rectal temp.Normal is 100.5-102.5 anything over 103 or under 100 and I would have her seen tonight in your local animal emergency. If her temp is normal I would have your regular vet see her tomorrow.
Until then try to keep her still and quiet, lift her food and water so she does not have to bend her neck to get to them.You can try using a heating pad on low across the
I hope all goes well. Please reply back if you have additional questions or concerns