A few weeks ago I was testing some 'broken' controllers that turned out to be fully functional but their cords had twisted and broken the power/data/ground wires inside. it turned out to be great for me since I'm making wireless controllers and now i dont have to rip apart any of my working controllers

. so anyway i simply chopped the cord and stripped it a bit and twisted the ends back together to make a working controller with a shorter cord... and exposed data & power & ground... which i let touch each other since i wasn't paying attention due to the delight of having magically repaired my lost controller.
here's what happened in the 1-2 seconds they touched:
random movements from joystick
LED flickered and went out, along with the picture
Me turning off the system and an immediate sense of dread
i turned the power switch on again but nothing happened, LED didnt even light up. i figured it was dead, but luckily this was not the case. i waited an hour or so after unplugging everything, then removed the expansion pack and turned it on for 10 sec. after that i plugged everything back in, put in a game, and everything worked!
its been working just fine ever sense so i dont think i did any damage, but I had no idea it was possible to (nearly) kill the system out from the controller port.
has anyone done something similar to this? any lasting damages?