If I Edited a post and later I noticed, that I did something wrong, can I revert it before it s reviewed?
When I've caught myself having made a mistake in editing without having the rep on the site to have my edits become publicly visible immediately, I head right back to the post and make another edit.
Maybe that isn't the best way to do it, but especially if it's a relatively small error, it seems better than cluttering up the edit history with yet another edit that should have been part of the first. The trick to that is catching the mistake quickly.
Of course, the original edit might still be approved or rejected while you are making the new one, which makes the second edit a new one (at least I think that's how it works). At least in that case, the post is (hopefully) better off after the edits than it was before your second edit.
You mean if you suggest an edit? No, there's currently no way to cancel them. If it's a bad edit it should get rejected though, and unless you make a lot of bad edits it won't really affect you, so don't worry about it