Sometimes dreams stick for no other reason that we find them annoying, and our minds will then latch onto that. Like, when you get a tune stuck in your head, it's more likely one you don't like....

Gotta tell about one of my funniest bathroom dreams, I dreamt I really needed to pee, and I was in an antique store someone I knew owned (In my dream). They went into the basement for a while so I grabbed a potty and peed in it and put it back on display! And when they came back the shop owner pointed out the potty (not noticing...) and said it was worth 3000 dollars! And I had peed in that! LOL.