Thanks for providing more information.
As you describe possible causes may include Occipital neuralgia,Cervical spondylosis.
As she is suffering from last few months so a clinical examination by your regular doctor/Orthopedist should be considered.
Further X-ray of cervical spine should be advised.
She should take OTC Motrin.
Also do gentle massage with muscle relaxant ointment and apply warm compresses with a heating pad on back of neck.
Physical therapy can be effective in her case.
As she has history of hypertension and now she gets shortness of breath so further EKG,Holter monitor,Lipid panel should be done to rule out any underlying cardiac pathology as well.
So make an appointment with your doctor ASAP.
I hope this helps.
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