Showing used space -but cant find where

[mk01]

ok, so :

edit /boot/cmdline.txt
find root=/dev/mmcblk0p2 and change it to root=/dev/nothing

reboot

you will get command prompt with error message (not important)

run "e2fsck /dev/mmcblk0p2"

then edit /boot/cmdline.txt again with those steps:
mount -t vfat /dev/mmcblk0p1 /tmp
vi /tmp/cmdline.txt

in the vi editor, you have to press "i" to start editing
change root= to root=/dev/mmcblk0p2
now:
press ESC, then ":" and "w". hit enter
then run
umount /tmp; sync
reboot -f