Hey, welcome to riu, & to growing. I think I agree that you're using too much fertilizer for that 1 little plant. Looks like it's leaves are burnt.
There are lots of forums here about plant problems & nutrients. Read up. Less is more when you're 1st starting out. Diffrent types of pot will like more nutrients than others. Try using 1/2 the recommended dose, until you get used to growing.
Unfortunately, reading & following directions can't prepare you for actual experience. There's a million things that can & will affect how well your plants come out. Don't count yer buds b4 they're harvested.
Good luck.