What Causes Discomfort In Left Arm And Left-sided Pain Near Spine?

For the last few days I ve experienced some discomfort in my left arm it feels heavy and numb almost like when your blood pressure is being taken. I also have an aching pain to the left of my spine near the center of my back I don t have any shortness of breath or feel bad besides that could it be a pinched nerve or should I seek immediate medical help?