hot soil or genetics..
First, it helps to use size-approriate pots. Makes irrigation a simple process. When watering a tiny plant in a big pot, you need to make sure that moisture is going deep enough that you aren't training superficial roots. You get weird drying patterns, you get potential buildup of nutrients where the moisture ebbs and flows away from roots - deposits solids, which then go back into solution when moisture returns, and over time that can cause some really fucked up concentration levels in areas where roots will eventually grow.
Second, seedlings often look a bit fugly... 'often' just means you should never be surprised by it. Nearly every hsc plant i've grown didn't look so great popping its first true leaves, lol, but tehy turn out well, nonetheless. So, i'd focus more on growth rate... as long as that's kosher, it's fine even if fugly. If you don't start seeing healthy leave growth within a couple nodes of growth beyond that point, then i'd start to have some concerns about deleterious mutations.
If it's the soil and it powers through, that too will present a healthier plant than before.
So, in either case, patience and good habits. If you use the same soil and continually see this sort of early growth, probably want to dilute that soil (flush with lots of runoff) or mix with something inerty etc... or use peat pucks / coco coir / rock wool to start. Just have to worry about pH with that stuff and seedling powers it's own growth first ~7 days anyway.
i use promis which comes with a ~500ppm charge. Light nutrient charges will not cause a problem. These seeds start in rich soil outside all the time, so it'd be a poorly evolved plant if it couldn't handle 'some' level of nutrients from the start... or terrible selective breeding, if they accidentally maximized a shit-ass trait like that, lol.