No you don't have to reinstall Raspbian, and it has nothing to do with your SDcard about to explode.
Here is how you can fix your filesystem that is in protected mode after an unsafe shutdown. There must be a better method, but this worked for me:
1. Check to see if you can
mount -o remount,rw /
2. Check your fstab
tail /etc/fstab
3. Populate your /etc/fstab
sudo echo -e "proc /proc proc defaults 0 0\n\dev/mmcblk0p1 /boot vfat defaults 0 2\n/dev/mmcblk0p2 / ext4 defaults,noatime 1" > /etc/fstab
4. Reboot
sudo reboot now