Certainly sounds like lightburn and heat stress. For a 2" plant they don't need a ton of light. They're stressed a little and will need a few days to recover. For now, leave light about 18" above garden, then lower a little at a time as plants start to recover. You can measure leaf temps. with one of those IR thermometers. The're cheap. A cheap light meter will be a big help also. I give cuttings about 3000 lumens(foot candles) from T-5's, 5000 for a few days after rooting, then build up to 10,000 for veg. When you change to HID lighting like your 250 MH it's much different than flouro's. More light and heat concentrated on a smaller area.