RQS - Northern Light Auto

I am a complete noob. Didn't add any nutrients until some time around 2nd or 3rd week of flowering. I write "some time around" because I didn't know she was flowring. I had noticed she was forming little pointy white pistils but still assumed tha tfloweiring wouldn't be until actual buds were forming. She seemed to be doing just fine except some older fan leaves showing yellow bettween the veins.