Schimmel oder Mehltau?

60 hours ago, I removed 3 seedling pots, and there were slight damages to the roots. I refilled the soil and watered the pots again. For the past 48 hours, the heads have been drooping (today they are standing straighter). This morning, I discovered white spots on the leaves. Mold or powdery mildew? What do you all think, and what should I do?