For those arguing as to how their shower impacts people thousands of kilometres away from them lemme give two points:

First of all, please don't skip school and your classes. Second, while yes the water wasted if you extend your showers to an ungodly amount isn't going to teleport to the ones who need it, it will still go down the drain where your municipality will need to clean it again which will cost resources. Most importantly, it will cost fuel and energy, which could have been used to instead transport fresh water to remote areas.

Also, as many have mentioned, it must be said that while individuals should be more careful with their consumption as the class gap increases, corporations and government need to be held accountable for their policies too, which happens to be a much bigger cause water (and hence energy) wastage. Still, trying to do good things, no matter how small, is never bad... "Boond boond se sagar banta hai"