I myself would prefer a shorter window between boiling and use time, but that's just me. More than likely, it's fine. Especially if the lid of the pot has any kind of a gasket on it like mine does (and the lid was placed over the boil pot to sterilize).
You could also use some bottled water from the supermarket (reverse osmosis or distilled) for your top off water, or you could add a campden tablet to your water to help the yeast take hold and dominate the beer. Remember, your goal is to sanitize so the yeast can take over enough to produce alcohol, not necessarily sterilize all the life from your brew setup.