Is this a preflower?

Nope -most likly buds ready to become a pair of new branches. I normally wait a couple of weeks then trim of tiny sucker branches at the bottom part of the plant. Flower forming on an auto usually start at the tip. She will sprout thin hair-like pistils.

hello.... not at all.... just a sign of new stem and leaves 👍 happy growing

Preflower is usually 4-5 weeks into veg. Seems early to me

not yet

It looks like a calyx. This indicates that your plant is a female, and that it is nearing sexual maturity. Expect white pistils from those, and some stretching starting next week as she matures into flowering :)