Elementary OS freezes on loading screen after update

Pio

Hi. After updating my elementary OS Freya 64 bit using update manager it freezed on loading screen. The only thing I could see was elementary OS logo and blinking animation and nothing else happened. My hard drive seemed to be idle. When I pressed ESC or ctrl + alt + F1 on loading screen I could see this message repeating a few times: scanning for btfrs filesystems end request: i/o error, dev sr0, sector 0 and it freezed. When I tried to enter recovery mode there were some messages and this one at the end: Btfrs info (device sda8): disk space caching is enabled.

I did sudo btrfs check --repair --init-csum-tree /dev/sda8 and now when I try to boot to elementary OS my keyboard LEDs are blinking and when I go to recovery mode I see this message:

kernel offset 0x0 from ffffffff81000000 relocation range end kernel panic - not syncing: attempted to kill init! exit code=0x000000100.

Is there any way to fix my system? What caused those issues?