Cogollos poco desarollados

Your buds look healthy, but autos usually don't bulk up as much as photoperiods; that really depends on the genetics. Heat can also slow down the bulking because the plant focuses more on surviving than on producing flowers. Plus, since autos have a short life cycle, if they don't develop enough growth structure, the flowers naturally end up smaller. You've done well with the pH, EC, and fertilizers, so don't worry too much. For future grows, try using larger pots, aerated substrate, and genetics known for denser buds. If you can protect them from extreme heat, that will also help a lot. From the look of the plant, I would say it has about 1–2 weeks left, but the best way to tell is to check the trichomes: harvest when most are milky and about 10–30% are amber. I hope you're giving the plants enough PK, as that really helps the buds bulk up. Also, for future grows, I would recommend topping the plant so you don't just have one main cola, and the hormones distribute better throughout the plant, leading to a more balanced overall development.