I don't know when this happened, but nothing shows up in MY COMPUTER under REMOVEABLE STORAGE. I have a card reader and a USB hub, but they don't show up. Their listed under device manager, but they aren't in my computer. So, I can't open up my card reader or camera or anything.
HELP

The first thing I would do is disconnect all devices, reboot, then connect the device again (perhaps in another USB port) and see what happens.

Note that this is often the result of shifting drive letters, caused when devices are installed and removed. Networked/mapped drives can do this too - those are drives on the network/Internet or another computer that you have mapped to and the computer has assigned a drive letter to.