What Causes Pain On Left Side Of Chest Along With Cold Sweats?

I am 21 years old, I smoke and drink heavily, I don t exercise and eat a lot of fast foods. Earlier I had a compressing pain on the left side of the chest along with pain in the left side of the neck and left shoulder with cold sweats nausea and light headedness. ECG (not treadmill) was normal but I sarted getting temporary spasms in the muscles of left arm moving the elbow towards the left side of the abdomen, the emergency doctor said it s just muscle cramps. Should I be worried? Could I be having heart problems? My family has no history of heart problems.