am i fizzity nucked?

Okay, THe other day my sub started making a rattling noise (a vibrating sound when it hit hard). I took it out and took it out of the box. There was a small piece of metal in the box (could have been vibrating). My question is, are there any ways to se if my subs blown w/o hooking it back up (im waiting on a new install kit). My subs peak power is well well well over my amps max power, so i thought i was playing it safe. any advice?