Right under the left side of my chest where you feel the heart beat i keep having spasms and tightness. it hurts my back and abdomen as well.

Chest pain: I always recommend erring on the side of precaution when it comes to chest pain on the left side that radiates. See your physician for a workup.

Chest pain: Your description makes the cause sound muscular. There are other structures besides the heart that cause similar sounding pain. If you have had chicken pox look for a rash. It does not sound cardiac in nature. Follow up with your doctor.

Without context...: ...its impossible to tell from here whether this was a physiologic (due to fear, exhaustion, overexertion, excitment, etc.) or pathologic response (e.g. tachyarrhythmias). Although what you describe may be noncardiac, never ignore chest pain and seek evaluation.