Anyone got a clue...

My dog chewed the power supply to this laptop a few months ago. I bought a recplacement on ebay. Has worked fine but yesterday, I stepped on it and it was blazing hot! So hot, couldn't hold it. I immediately pulled the plug and ran the laptop off the battery until it ran out of juice.

Today, I am plug powered again and note that my laptop... the fan has quit running all the time.

I am curious if perhaps the culprit is not the hard drive but... could the power supply be going bad and have made the hard drive act weird? I guess too early to tell what is going on here. I have it backed up.