advice neede.plant turning yellow,purple spots(pics!)

Hey all riu members.
So my plant is turning yellow and i see some purple color on the top of the stem.whats that.im not over watering and not using any nutes because im a little broke right now.
Can you tell my what should i do and what organic stuff i could find, lets say in the woods or somwhere else(need N).If you could help and give some advice, please do that.

more light and try to put some perlite in your mix when you repot it

Nitrogen Deficiencies:
Plants will exhibit lack of vigor, slow growth and will be weak and stunted. Quality and yield will be significantly reduced. Older leaves become yellow (chlorotic) from lack of chlorophyll. Deficient plants will exhibit uniform light green to yellow on older leaves, these leaves may die and drop. Leaf margins will not curled up noticeably. Chlorosis will eventually spread throughout the plant. Stems, petioles and lower leaf surfaces may turn purple./ hope it helps

You really need N and fast. Perlite aint going to help for the guy that posted that... good luck.

yes yesw-nice info guys, but what can i use what i can find around the house to help my plant out???

use your own piss, like 1/10 (piss to water) but make sure you've eaten healthily for a few days before.

Me, never done it, but it does work for many and if you're desperate.

Also, there's fish parts. Go fishing and blend some up but dilute it very well.

ok man-today i went to my local shop and there was this lillte flowering shop next to it.i went in and buyed 1l of some plant food meant for tomatoes and quecumbors.it also has fe and br.i dunno-looks fine to me.also i transplanted my shitty looking clone to my outdoor plot.and i puted my mini greenhouse bottle on top of it.hope it works cas I just heard on the news that there are going to be some cold night.