stereo problems

hey, im new here so please bear with me

i was recently installing a new deck in my 97 malibu, and started playing the deck and testing everything out. After about 5 min. the deck just shut off and wouldnt turn back on. I reinstalled the origional stereo and that wont work either.

There are a few things that i think could have happened
1. the antitheft system on the stereo kicked in (which makes no sense why it wouldnt allow me to install a new deck)
2. I blew the fuse (which would also raise the question of why are the lights and clock still working on the stereo)
3. I used the factory harness that fit into the aftermarket harness that i had from my previous vehicle

if someone could give me their opinion of what has happened or what i could do to fix it, it would be greatly appreciated.

Thanks

sounds like #2