In the middle of flashing my little sisters DS Lite (using FlashMe), her thumb it the power button. Here is a little reenactment:
Startup DS
Select the FlashMe Homebrew icon
Press X,B,X,B (like it said to)
The progress beeping started
beep beep beep beep beep
BEEPBEEPBEEPBEEPBEEPBEEPBEEP-...(silence)
Me: eek...


sister:

in my mind: (Wait, FlashMe comes with fail safe code!)

Startup DS (nothing)

Startup DS (pressing start+select)
My DSTT loading screen comes up...

Waiting...
Waiting...
Waiting...
Nothing.

Does the DSTT need the DS Firmware to start? My AceKart 2i is coming in a week, so I hope that will work without the DS Firmware...
Is there any other possible way to get my DSTT to start so I can repair my sisters DS?

Also note that it can still play games though..
Thanks to anyone who answers! My sister thanks you too!