What king of Lights are you using? A lot of people will tell you not to use Miracle grow, but it is all right as long as you flush your plant Two weeks, before harvest. You might have an Auto flowering plant, they give no warning, they just start the flowering stage when ever they want to. The catus 2-7-7 Miracle grow is good for the flower stage, and the 8-7-6 for the veg. You really need to give a little more information on how much space and what types of light's you are using, before some one can help you. Don't know what kind of soil you are using, but the next time, try to put some rabbit poop, and some lime mix in with it, most people will tell you to stay all orginac. Good luck, and happying growing