Just get the nutes man, youve got 3 months invested at least and you dont have even 8 to get a bag of cheap bloom fert? how long has it been flowering for? where do you live? im assuming its outside? what kind of soil you got?
I'm in Florida it's outside I let it outside till it was 2 half months old then I started to bring it inside for 12 off then outside for 12 on I took soil from my earth box it was my moms so I really don't know
add nutes man!
i use simple Fish Emulsion for vegging (high nitrogen) and a phosphate powder for flowering. you can get enough to last your whole grow for under 15 bucks