I checked the water runoff last night after I read your advisement above and it was 595 ppm so it looks like I might be ok. I'll pay particular attention to this in the future. Over the last few days the upper leaf tips are curling down a bit but there is definitely no yellowing around the leaf edges. Thanks for the baby analogy which makes sense.
I normally feed my autos at 600ppm about week 6.
That chart i put on for you,is for regular plants.I go for 1/2 these figures to start with,
and i can up them if the plant tells me to.
Your leaf tips curling down is a sign of overfeeding.
If it gets any worse you need to get some of those nutes outa there.
Lets hope it doesnt come to that,coz as i said earlier,this is a crucial time of an autos life.
If they dont like the amount of Nitrogen your giving them,they can and will stunt.
Ive had plants that didnt like 300ppm at 3 weeks old.
Hopefully your plant will be ok,but keep a close eye on it.
GL