Yeah, that happened to me. i thought i couldn't fix it. you are lucky you only got the pad, most of the time when you pull the pad, the wire in the motherboard comes along with it. there are two ways to fix it.
the first way, is follow the wire on the motherboard, in the opposite direction of the pad. when the wire eventually gets to a part with solder on it, solder a wire to that part and solder the other side of the wire to the led. im not sure about this since they are leds and all are different because they indicate if your player 1 2 3 or 4.
the second option is if you have the wire in the board still, get a xacto knife or a box cutter or your finger nail and gently scrape the light green part of the motherboard that leads to the pad. scrape untill some of the coating comes off and you see a very small wire that is gold/brown. make sure you scrape lightly or the hole wire will be cut out. then get 30+ awg wire, the smaller the better 30awg may be hard for some to solder onto the small motherboard wire, then cover the 30 awg wire with solder. then try to cover the motherboard wire that you scraped with solder. the more coating you scrape off the better. then when you've added solder to both sides, line up the 30 awg with the motherboard wire and heat the wire up for 1 second or less. if it sticks, great, you may want to add more solder when its attached. then solder the other side of the 30 awg wire to the led.
you will never be able to put the original pad back in unless your an expert at motherboard repair.
hope you get it fixed!
good luck
i would take pictures if my camera did not suck
im sure they have tutorials somewhere on how to do this.