Go ahead and flush that toilet. I have some great news for you, there is nothing suspicious about flushing the toilet in the middle of the night. Your parents aren't going to suddenly wake up thinking, "what the hell is that little bastard up to, flushing toilets and what not?!".

I know back in my high school daze when I first started toking, I would sneak out to smoke a bowl, and if I needed to use the bathroom before I crashed out I was always so scared to flush the toilet because I thought it would wake my mom up and she would for some reason come find me because she heard the toilet flush and bust me for being high. I always justified it, ya know, if it's yellow let it mellow. But anyway, enjoy the early days, you will always look back and smile.