CD/DVD drive won't load disks...is it dead?

The HL-DT-ST DVDRW GA11N drive had always worked with no problem. There was a CD I left in it (without playing) for a couple of months, and when I tried to eject it, the drive kept trying but it would not eject - - a tiny bit of the edge would peek out momentarily, but then it would get sucked right back in, after which the drive would spin up and the disc would reappear in the Finder. After repeated attempts to eject it (including using Finder, iTunes, and Terminal, and restarting the iMac), I was finally able to grab hold of the tiny bit that showed on one eject attempt and forcibly pull it out. That may have been a mistake.

Now, attempting to insert another disk results in absolutely no reaction. It will not trigger whatever is supposed to sense a disc is trying to be inserted. Is the drive dead? Am I pretty much screwed and left with no choice but to hook up an external drive or take my iMac to the Apple Store (where it is out of warranty, of course). I cannot find any way to test or check the status of the disc drive in the built-in disc diagnostics.