I Just Experience What Felt Like A Muscle Spasm In

I just experience what felt like a muscle spasm in my across my chest, right at the bra line . It was painful..felt like a muscles were being squeezed. I didn't feel it in my back like heartburn, just the front. And not on one side but the whole chest. No other pain anywhere else. no trouble breathing. it lasted about 5 mins. it happened on Friday too for about 2 mins. what could it be?