You might want to try your Amazon Fire Stick in another device. It could be that the HDMI port that it was plugged into could have gone bad.
Try it in another device that you have access to that has an HDMI port on it. And change out the charging cable with another one that you know works. Pinning down problems with an electronic device sometimes takes some extra "creative work arounds".
If all else fails, I'd contact Amazon support for Amazon Devices. Hope you get your Fire Stick working again!