News:
I managed to fix that issue by entering safe mode and repairing some permissions on my disk ( it was something about the BootCamp Util itself).
New Problem:
I finished making the BootCamp Partitition, my MacBook rebooted and it appeared on the screen: No Bootable Device, even though i did have my Flash Drive with Windows 7 installation on it. Now, what should i do? Try re-doing windows installation on my Flash Drive? And then what? how do i boot on it. As BootCamp now shows "Remove Windows 7" instead of "Install windows 7"