Can you provide more details?
Since how you have this sore spot ?
Any signs of inflammation, discharge,itching or scaling?
Is it some kind swelling or bump which you are feeling below skin? Please describe it.
From details and symptoms described by you its difficult to predict exact cause of your pain. There are multiple structures located at this site, like thyroid, carotid vessels,neck muscles and lymph node etc. And as you described it as pulsating it can be related to blood vessels or in close proximity of vessels.Pathologies of any of these structure can give raise to such symptoms.
Usually such cases like yours are investigated by neck sonography and then if required CT scan. I guess you should consider a primary evaluation by GP doctor ,who can clinically examine you and guide you regarding further investigation , specialist (if required) and treatment.
I hope I have been helpful to you, Please ask if there are any doubts.
Please click the ‘ACCEPT (Green) Button so I get credit for my time.
Thank you. Regards