This could be a sign of high blood pressure, and if so, there are potentially serious health implications.
Blood flows to the brain via the carotid arteries, which run up the neck on each side of the throat. If you look upwards, to stretch the soft tissues in the neck, then place your finger-tips parallel to the throat alongside the larynx (voice box), you should be able to feel your pulse.
However, it is unusual to be able to feel the pulse so strongly that you are aware of it without deliberately feeling for it in the manner I described.
Fit and healthy people may be aware of that carotid pulse beating strongly immediately after very vigorous exercise, but if you can sense the pulse during relaxed sedentary periods, it is perhaps a little worrying.
High blood pressure can be caused by such things as poor diet, inadequate exercise, obesity, and elevated stress levels. The danger is that it can lead to potentially dangerous conditions such as thrombosis, stroke and heart attacks.
I recommend that you consult a Doctor about these symptoms and if your blood pressure is indeed found to be abnormally high, follow his advice regarding life-style changes (typically dietary changes with an improved exercise regime) and if necessary medication.
Good answer.............I'd like to add that another problem becoming more common is atrial fibrillation (heart out of rhythm) it's an electrical thing. It used to happen to me all the time and would always go away. One time it didn't go away and I almost stroked out....Thank God I went to the ER "that" time because it saved my life. I just take a pill now and it takes care of it...............Get yourself checked out is my advice.