NO, you can easily get data back from this formatted SD card, you get a data recovery software for your system and then use it to recover your files.
these days, the data recovery software is common and easy to use.
you should notice that you can;t write anything new to the SD card, keep it original.
I recommend one data recovery software for you, if you are running Mac OS X 10.5/10.6/10.7, try EaseUS Mac Data Recovery Wizard, you can free download to have a free scan, if you find lost files using this software, then you purchase it to recover.
If you are Windows users, try EaseUS Data Recovery Wizard.