What brand/type of soil? Did you just start feeding them? They don't usually need food until week three from seed so hopefully you just started feeding. Get bulbs at www.htgsupply.com or www.1000bulbs.com You might wanna get a cheap pH tester or meter. Check htg for that.
i really do think its basically nothing. its like when sometimes the leaves grow all twisted, just a natural occurrence, a unique thing that just can happen sometimes to me it just looks like the leaf has not grown enough cell wall there and has been a little burnt it really is nothing, just individual scars