I was 134 yesterday but i ate way to much food (including ice cream, cheerios, chili) i gained in one day to 136. do you think this is mostly water?

What does food weigh: It takes 3500 calories to add one pound. By consuming 500 "extra" calories a day for a week, you would add a pound if nothing else changes. Weighing yourself daily can be deceiving. Try weighing yourself once a week, first thing in the morning, wearing the same clothes, and trend it. You're right that a sudden increase can be from water or the bulk of food left over, but look for the long haul.