Have I really gained weight or.?

So I weighed myself yesterday and I was 110 pounds (what I've been maintaining for about a month now after losing weight) I have been eating a bit more and being more lenient with my eating now that I'm nearly at my ideal weight for my height, but no major difference really. I just recently weighed myself and I weighed 115? Is it possibly just a water fluctuation in my body? I did drink a lot I guess and maybe haven't passed everything through. Please tell me what you think the sudden scare on my scale is about! I'd greatly appreciate it!

Weighing first in the morning is ideal because you have not eaten any solid foods or water. Weigh yourself about twice a month in the morning and see how you do!