the stem looks a little thin, but otherwise your ok...DO NOT OVERNUTE!...you are looking good...I would advise using a little less than suggested in mix, so you don't overnute...
1. what lights are you using...get a fan to exercise themand keep them cool (very important) and make sure that your light is close enough to the tops to keep them from stretching.

2. what is your potting mixture?...get some superthrive and water with superthrive in ph'd water 6.5 in between baby bio, this will also help keep you from overnuting...
the #1 killer of baby mj is overwatering and overferting...it is a weed leave it alone and it will grow...more later.lw