History:

• May 4th: The marglobe tomato seedlings in the photo were sown indoors in 12-cell grids, two or three seeds per cell.
• May 18th: They all had their first set of true leaves, and they received their first "indoor" dose of fertilizer using Miracle Gro water soluble all purpose plant food at a concentration of one-half teaspoon per gallon of water, which should produce a ratio of 3-1-2.
• May 19th: Their seed leaves had turned yellow, but their true leaves still looked normal.
• May 23rd: Most of the seedlings were looking pretty sad (wilted, drooped over), and the soil was looking pretty dry, so I gave them another round of watering, this time with plain water (no fertilizer), and within hours they were back to looking happy again.
• May 26th (today): Back to looking not normal but in a different way. Many seedlings' true leaves are folded upward, and the two seedlings in the front-right cell are wilted and drooped over again. I gave them another shot of plain water (no fertilizer) this morning since the soil was looking dry again.

All waterings, including today's, have been bottom waterings, where I lift the cells out and pour water into the bottom trays, then dump any excess after about 10 minutes.

Questions: Did I give them their first feeding too soon (at two weeks old)? Are seed leaves' yellowing and true leaves' folding upward a sign of nutrient burn? Should I flush the soil w/ plain water to flush out the fertilizer from the 18th?