O.K. Thank you for the additional information.
I think you should see your physician at this point. This could, potentially, be angina, an indicator of heart disease, as sometimes people experience pain like this that is related to heart dysfunction. While many people also experience chest pain/ache/"tightness", shortness of breath and the other symptoms I mentioned, some people do not, and only experience the arm and jaw pain. So, to err on the side of safety, you should see your physician about this to at least rule out any heart-related etiology.
They will be able to do some simple bloodwork, and an EKG, and perhaps other testing as well, to at least rule out the heart as a potential cause.
If the heart is ruled out as a potential cause, then this could, instead, be a problem related to your cervical spine (in your neck). If one of the discs herniates or protrudes out of place, it can put pressure on the nerves that supply your arm, jaw, and neck.
But I think that, first and foremost, the potential for any heart-related cause needs to be ruled out. So make the call today, and get into see your physician immediately. Tell them you're worried about your heart and that this might be angina, and they should be willing to see you. If not, then get into the emergency room. Better safe than sorry.
I hope this helps. Please let me know if you have any further questions - I'm more than happy to try and help.
Take care - Dr. Fay
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