I'm a 53-year old woman, having left-arm pain attacks. bad. they come and go. some swelling in the left arm. pain also in the left shoulder and upper back. sometimes pain in both arms. some tight feeling in chest. some shortness of breath. have had these arm-pain attacks while under stressful situations and at rest with no stress. happen suddenly. the past nearly three days these attacks have come and gone. I'm wondering if I'm having an off-and-on again heart attack. is that possible? .