Woah, Instead of feeding again, what you should do is flush all of those very very well with plan PH'd water..... completely... Then after a day or two, watching soil moisture level, and reactions, on the next feeding start with some readily available nitrogen (nothing slow release.) Then again, after a day or two checking moisture, and reaction, Then MAYBE consider adding some of your nute cycle feed.
Also, those seedlings are experiencing the same exact thing it looks like... Seedlings should have plenty of nutes for the first few weeks, long enough for them to get bigger than that, then start with a heavier than water feeding...
Lighten up on all feedings and only do it when it seems like she needs something. Sounds like your adding too much to fix existing problems and instead just causing more and more.
Plain PH water... do it til they recover, once they do, then start with the feeding... But for now, Flush very well to get any potential lock out of nute in your soil, out.
Good luck, keep us updated.
