Why she's sad?

in your diary it is in preflower already, this auto was shocked or is just shit and entering bloom at such a younge age and little to no height. I would get some new seeds going as this one will not amount to much of anything.

Everything looked good till week 2, you added mulch to a already tropical environment. 70rh% , plant needs 0.04% of co2 in air not the 75% moisture floating around taking up all the real estate. She is a seedling....... no higher than 77f ambient until she is etablished. Bacterial growth explodes x10 above 77f which is something to consider, especially when you run high rh environments. It seriously ups the stakes and is unforgiving to mishaps or oversights when it comes to tent setup. 75% at 80F is insane amount of moisture for a inexperienced grower and will lead to problems over time. When that temp drop at night that 70rh is just climbing to 80rh+ easy. Adding mulch to a waterlogged medium with no way to evaporate or uptake due to high rh and almost non existent gas exchange. Alrdy she has started to cannibalize nitrogen in old growth, no way in hell she is deficient so soon, means she either can't release water at night or ph has drifted out of range and plant decided to use pre existing nitrogen in order growth for new growth. Good luck.