Sorry to hear about the injury, Pekka.
Knee injuries hurt like stink....having ruptured/avulsed my ACL two years ago, I know. After an ACL reconstruction with a patellar graft and the addition of 2 hefty Titanium fixtures, I am better than ever....so there is life after an injury!
---Did you rupture your quadriceps?
Sounds like you got a righteous injury...
donmoore is right: a good physical therapist can help you recover if you stay within the parameters of what you are told and follow directions exactly. Being a 'hero' and pushing an injured knee beyond reason will keep you on the bench longer than you can imagine.
Hope you feel better and make a complete recovery.