As long as NPCs will still talk and trade with you a low reputation doesn't matter (any merchants you trade with a lot will have a maxed opinion of you regardless of your base reputation, and no quests, etc, require a certain value).
If the save before then is recent, though, you might as well reload (ie if you wouldn't loose a lot of time or great loot). Guards treat you better with a higher reputation (not sure if it effects other dialogs very much), and it helps a bit with prices.
