I've asked a question and after some edits I fatally and inadvertently changed it to community wiki.
Is it possible, using rollback, to return to the point where community wiki flag is not set?
No, it's not possible.
Once a post (either question or answer) is marked as community-wiki, that cannot be rolled back. Please see the appropriate FAQ question.
If you're able to delete your question, you could do that and re-ask as non-CW.