I take it you wanted to upgrade to 3.3.4 (not to 3.3.5 which hasn't been released yet)
The correct way to upgrade is described in
Upgrading from 3.2 to 3.3
(which is actually mentioned in the download area:)
If updating from phpBB 3.1.x or 3.2.x then please see our guide for the recommended updating method.
The most simple way to restore your board would be to put the files back and to restore the backup you made (it's more work than absolutely necessary but is less complicated that the fast way).
Once your board is back in the state it was before you used the autoupdate, use the Full Package method (and remove the /installer and /production from /cache AND io_lock.lock and install_config.php + any migrationsxxx from /store if present.
Then navigate to your board /install and run the database update only.