Upon attempting to go back to bed at the beginning, saving time. I instead get the message: Your bed. Does anyone know why?

Not sure if you can use the bed in C2 to skip stuff, but if you can, you must complete the game before you can do it.

you have to have a completion file in your deltarune saves folder (normally at C:\Users(your username)\AppData\Local\DELTARUNE on windows) in order to do bed skip; the saves that you can download in the resources tab include completion files if you want (they're named filech2_3)

As mentioned earlier, before you can skip the part with school, you have to pass the game at least once.