The first thing you need to do is to stop doubting the Wudhoo. That's from the Wasaawis (whisperings) of Shaytaan. Once you have made Wudhoo, it's done, you have Wudhoo, and you must know perform Salaah if the time has come in.
By late, what do you mean? You performed Salaah five minutes after the time for Maghrib had gone out, meaning it was now time for `Ishaa?