Good. Then you should try to rename the original .img file back to what it was. However, do not use the command with "uname -r" because that would use the older kernel you are currently running, and you would still not have a valid initramfs file for the newer kernel.
Best thing would probably be to rename the /boot/initramfs-<kernelversion>-nouveau.img file in place, removing the "-nouveau" part. So it would be
Code:
mv /boot/initramfs-<kernelversion>-nouveau.img /boot/initramfs-<kernelversion>.img
where <kernelversion> = the version of the newer kernel.