I don't understand why some bottom leafes are turning yellow. I've feed them just a few times, the first on 1/4 strenght, the second on 1/3 strenght and kinda keept it there. There in normal potting soil Ph 7. I'm gonna make them flower in 10 days, hope it's not too early. Could it still be a burn or could it be something else?
Those things look exactly like mine started to look before I transplanted them. They were about that size too and when I took them out of their pots, which are the same you're using, they were root bound. Give those girls a little more room and when you transplant them, lightly score the roots on the sides so they'll branch out easier into their new medium. It worked like a charm for me.
I'm not so skilled at diagnosing problems yet, but this is an easy one. that is nitrogen def. your ph is slightly high, but certainly acceptable. you may have a build up of organic salts in your soil from the ferts, have you tried flushing? flush your soil by water with about 3 times as much water as soil.
I already transplanted them once, but I don't have any space left so I'm gonna have to keep them in those pots. Is it ok if I make them flower in ten days or is it too early? I dont have much of a choice since they have to be ready by may.