Hi Sara,
Is there no dirt on the light sensor (only on the N1)?
If you disconnect the cameras, does the N1 turn on? This is to rule out the possibility that one of the cameras is defective and is causing the N1 not to start up.
If you reset the N1 by removing the power (just taking the fuse off for a few seconds), what happens then?
If you have the N1 Pro version, can you press the reset button? It is located next to the SD card slot.
Can you still connect your phone to your N1? If so, then there is probably a problem with just the screen.
It is normal for the N1 to get slightly warm (hand-warm), but it certainly should not get hot.
Since your N1 is still within the warranty period, you can also contact the seller and claim this problem under warranty.