Rereading the scratching at the door post it seems that the night(s?) before Daniel heard the scratching he stayed up late, could just be a coincidence but it's worth looking into. Just don't pull too many all-nighters, my max is like 2 before I pass out on the third day.

However, I doubt it's just the act of staying up because if it was there would be more college students dealing with the scratching so maybe it's something he did during the night (Played video games/did homework/etc.) It's interesting to note that once you hear the scratching you're kept up by it so maybe the lack of sleep is what makes it gro. Typing all this out reminds me of the phantoms in Minecraft which grow in number the more nights you go without sleep.

It doesn't seem to be restricted to one dorm building so I'm assuming staying up in your dorm might work.