Water weight or weight gain?

So yesterday I weighed 132.6 and I went to amusement park I usually eat low fat/carbs and high protein. I had to eat at the park so I opted for chicken tenders and some fries I had two tenders and a couple of fries then today I had class and had a chicken quesadilla... I weighed myself on the scale before and was 135.. is it from weight weight? I didn't get much sleep and I was dehydrated, do you think it was just from that?