Had slurpee 1 drink "froze"mid chest area in pain for several minutes (about 5-10)was hard to breathe. should i be concerned? if it occurs again?

No: This happens to almost everybody. If the breathing trouble was from breathing being uncomfortable, probably some of the ice got stuck, paralyzed the esophagus for a bit, then eventually passed. Try sipping and savoring the icy treat more slowly, but don't be frightened. Now, if the shortness of breath was like you were running a marathon, i'm concerned; tell your physician, r/o coronary disease.