Hi there Turk ! so yeah a few things happened first the over watering, which is an easy thing to do with such a small pot ! second , for whatever reason it seems the overwatering flushed out the nutrients in the soil, which has led you to a pretty much text book Nitrogen deficiency. Finally, i'm a bit worried about your pot size, it's pretty small for a cannabis plant, this might lead to the plant being root bound. It's a bit late to repot an auto, but you should repot anyway and pray it fixes most of these problems. hopefully you'll give the plant a new home just in time for the flower stretch. Time is of the essence, and i'm sorry i can't give you better news, but that's the truth. To fix your cal mag problem (if the bigger pot doesnt fix it), make a calmag solution 6ml/L and spray until dripping wet daily for a week, that should fix it. Hope this helps my friend ! 🚀