Don’t worry! To format your write protected SD card is not a difficult task:
1. Remove the write protection:
http://www.itrelated.info/remove-write-protection-from-a-drive-memory-card/
2. Recover the inner data at the aid of a memory card recovery freeware, if you do have important data on it:
http://blog4mark.blogspot.com/2013/01/memory-card-recovery.html
Normally, before you do any change to the inner data of your SD card, you are supposed to back it well at first. But, if you cannot do it somehow, especially for some error warning, you also have no need to worry. This time, you could try this freeware to restore all your data back and then back it up.
3. Format hid drive:
My computer=> right click your card=> Format => Quick Format
Note: If the reformat process cannot be completed after recovery process, you can try some format tool, such as HP USB Disk Storage Format Tool
Good luck!