Why does she look so different when compared to other diaries of this strain?

It has entered early flower. Autoflowers sometimes do what ever the fuck they want. It will not be getting much bigger. This normally happens from stress, autos really don't like root stress and that can set them off. its why transplanting is not recommended or other HST things like topping. Other things that can set them off is temp swings or to much feed. So that's the reason it look so much more different. I would pop another seed and start over. I also find some auto strains from fast buds are harder to get going like LSD but other ones are more forgiving like OG Kush. Kinda of a cointoss till you try it out. Good Luck!