hi
my aprtner wanted to see if we could grow them so we tried ( all new to gardening really) i left thim in a tray on the window sill and the came up just as quick as yours, after that the leaves just kept going and about 3 weeks ago they got planted out and noe the leaves are bigge than my partnners hand and have about 3 buds per plant.
i did read about them before planting adn it seems they go crazy like teenagers and keep gowign VERY quickly.