We planted supatiens in containers a week ago, good drainage, good water. Some plants are starting to show some discoloration on leaves. The last 2 nights have been colder and the forecast has 3-4 nights of mid-upper 30's coming up. Could cold temps make them discolor, should I bring pots in the garage for a few days?

Yes, any impatiens are sensitive to the cold and will not tolerate temps less than about 35' -40 'F, especially when they are newer. Did you harden them off gradually when you first put them out as well? Both could contribute to leaf discolouration. I would bring them in definitely on the cooler nights; put them out in the daytime if the weather is warmer. Good luck.