How can I take care of neck and jaw discomfort?

Check your bite. Neck and jaw pain may be signs of problems with head position, bite problems and postural issues. Neuromuscular dentists and atlas orthogonal or nucca chiropractors and osteopaths may be worth exploring.
TMJ. Classic TMJ symptoms. See a TMJ/TMD specialist. Any dentist can be a TMJ expert with the proper training and experience. Most commonly, oral surgeons, prosthodontists, and orofacial pain specialists. Ask your MD, your dentist and your dental society for referrals.
Careful Exercises. Often caused by bad alignment, or tmj, if dental, correction is indicated. Isometric stretches such as biting a hard rubber ball gently, and massaging cheek muscles, or pt skilled in this help. Avoid stress on the jaw by chewing symmetrically, not using gum. Neck pain can cause spasm and jaw pain. Strengthen, improve posture and work on flexibility. Manage stress and relax. Get help when needed.