SD Card is damaged try reformatting?

So I've had my Unrooted Evo pretty much since launch day, and this morning I keep getting the message sd card is damaged try reformatting, or it will say sd card has been removed. When I check my picture gallery all of my pictures are there. When I check the sd card in the storage area it say unavailable? I keep getting this message about every 3 minutes or so I've tried removing the card and replacing it, I've tried rebooting the phone sometimes the message will clear itself only to reappear minutes later. Any one else ever had this issue I haven't tried reformatting because I don't wanna lose my music, the pictures are backed up on Google so really don't care about that. Any help would be appreciated. :'(

SD cards do fail eventually so it could be that.

Have you tried the card in a different device?

Thanks Darth Mo I guess maybe that's what's happening, no I haven' tried it anywhere else yet.

Now the strange thing is when I removed the card all my music and pictures which I thought was being saved to the sd card is still on my phone? When I try to copy a picture from a mms message to the sd card it give me the option says it saved and it is in my phone under downloads even without the sd card being inserted? So I'm guessing this card must have been corrupted from day one, and all the time I thought I was saving stuff to the sd card it's really been saving to the phone? I don't it?

Yeah it's weird. You have "App Storage" and "Phone Storage" that share the 16 GB of memory on board. They changed the way Android handles internal storage in ICS.

So most of the times when you save something to SD card, it's actually going onto that Phone Storage partition. For example, "Move to SD" for apps puts them on Phone Storage. You can't move apps to an external SD. You can only save photos and videos to an external/removable SD card. So if you never manually moved anything over, it's likely you never used the external SD.