Hey there! You should get rid of your pain first. There can be different number of problems causing the "cervical" "region" pain. One of the reasons being, loosing a lot of weight at once.
Getting on diet, such as keto diet, and loosing weight at once; can turn out to be problematic. Body fat and "cushions" of body parts disappear, spinal alignment affected. Muscles can get into spasm.
Firstly, diet change, and then vigorous exercise routine. Our body cannot cope up.
Next Steps
Get checked first. Take proper diet. Proper healthy food matters. It seems that you have chronic cervical spasm.
Health Tips
please do not name your problem as "cervical problem". Cervical is a region of spine. The cervical "region" of spine can have many issues causing the pain. You should be aware of that issue and get it treated first.