Pilz oder Mangel?

Hello, for me it also looks like a beginning calcium deficiency. But as my predecessor already said, it's still hard to tell in the early stages.

Guano is very strong (extremely high phosphorous) and giving it to such a small plant may be the cauase, especially if you splashed some on the leaves. I would not be too worried, it will not effect anything, but I would avoid using guano at anything more than one fifth strength and no more often than every 3 weeks on a plant that size. Anyway, it is not a fungal problem. If you are a new grower, I suggest you visit the "Mandala Seeds" website and read their "grow guides", it has a huge amount of excellent information with a good focus on European products (and North American too)....you will find the grow guides most interesting!

Could be the beginning of calcium deficiency. It's not noticeable in this early stage yet.

It doesn't look like fungus or defect to me. Maybe pH or nutrient imbalance. I wouldn't do anything just yet.

looks like you have been spraying something on that plant by my eye or got feed on the leaves its probably a cal mag problem but there's no way to tell yet until she is slightly larger but yeah flowering this early I can only assume its an auto or not got a good light source :) anyway best of luck buddy.