Stereo & Electronics - radio not working

so i was putting my system back in my car after a road trip (put factory radio in) got everything hooked up and working subs were not as loud as usual. but anyways. it just stops lost power for sum reason idk. but not even the factory radio will work it has power running to it cause the clock and lights work the radio will not turn on and it doesnt say LOC like the owners man said so its not locked. idk if anyone has had this prob before or any ideas of wtf is going on with my radio. also ive swapped back to stock more than once and everything worked fine before so idk. im kinda stuck. thanks

oh also when i turn the key back to acc it dings twice and the seatbelt light flashes twice with the dings. idk never done it before