You are having symptoms that suggest a possible cardiac problem. Typically, the presentation is "left arm". You need to go to an emergency room immediately. You have a "ROMI". Rule out myocardial infarct. Now before I hear all the criticism from the peanut gallery, left arm numbness and symptoms are the textbook presentation of such an event. The cold sweats, however, are often connected with insufficient oxygenation of the heart muscle. It may be nothing. It may be a silent MI. It is IMPOSSIBLE to tell and present an opinion via the net. Unless you are into russian roulette, however you need to see an M.D. as of yesterday, preferably in an ER, rather than an office setting, where they can perform such tests as a cardiac enzyme evaluation within minutes.
if you are having this problems you know that you should see a physician.