Cannabis goes into flowering, as a reaction to the hours of daylight getting shorter, and nutes don't play a part in that. So, no need to worry about that. We'll need some pics, because it's almost impossible to suggest anything for your problem, without visuals. The best I can do ATM, is say that it's possibly a magnesium deficiency, based on those yellowing tips. Other than that, I'd be blindly guessing.
Do you know what that "stuff" actually is? Is it fert? Root hormone? Jack Daniels? Hydrochloric acid? Frog eggs,....(okay, I'll stop.LOL)