Bitcoin core database gone after error no more free disk space? How can I recover my bitcoins? So I got myself into this situation.

I have a Bitcoin core wallet, which was up to date and all the way synced. Two days ago I tried to start it up again but when I tried to shut my laptop down I had a notification that I had no more free disc space, so Bitcoin core automatically shutted down. The day after I started my laptop again and the program was gone from my start task bar and had to go search it manually in program files. To my surprise when I opened my wallet it had to restart synchronizing all the way back from the start again. Not only that, all of my database directory was gone from the %appdata%\bitcoin folder! It started everything back from the beginning.

Of course I couldn't as I had no more free disk space. Now the strange thing is, all that space on my Hard drive went to the bitcoin database directory. But if my files are gone, and I still have no free disk space then where are they now, are they stored some place alse or hidden? Or did my hard drive crashed? If they where permanently gone I should have had free disk space again.

How can I solve this and recover my bitcoins? Please help, I'm freaking out as I'm afraid I won't be able to recover them any more as all my dat.files are gone!
This is not a complete answer, but the question implies a possible misunderstanding which this attempts to correct.

Summary: if you can rescue wallet.dat, you're fine.

The only valuable file in the Bitcoin Core user system is wallet.dat. The blockchain files are necessary for the application to be able to see the transactions on the blockchain that sent bitcoins to you and to figure out how many bitcoins you "own" (can spend). What is actually in wallet.dat are your private keys, which is all you need to have.

If Bitcoin Core doesn't have access to the blockchain data then it doesn't know that you have any bitcoins. Once it has access again -- after re-downloading (takes a long time!) -- on this or on another computer, you will be able to see your bitcoin balance.