Sorry to hear about the little guy. Sadly it sounds like it wasn't in the best shape when you got it if it went that quick.
My boyfriend was given two tokay's about a year ago. A male and female. They were both so skinny from lack of care. We were able to get them nice and healthy looking but suddenly the female passed away a couple of months ago. We still really don't know why, but luckily the male is still doing great and nice and big.

But for geckos that like to bite they are pretty cool. Here is a pic of the male we still have.



Did you talk with the person you got the baby from? Hopefully if it was from a breeder or even a pet store they'll return at least a part of the money you paid for it. Plus they might want to know if they happen to have it's sibling and want to keep an eye out for it.