Redden Leaves

hi guys,
I dont understand what is really going on with this plant.
At first the stems are redden, so I thought it might be p def.
5 days ago, feed it with 13/14 pk,
however, right now, even middle fan leaves turn red,
lower fan leaves turn yellow, so N def, might also be another problem.
I suppose 4th week in flowering, maybe 5th
I am sorry pictures are kind of blurry, the best I could take right now.
Also, it is fuma con dios and early durban cross from flying dutchmen, so sativa dominant

Red, I'd say P as well. So if you fed them that and they didn't absorb it what is your pH? The medium etc... At this point I'll post my usual request for full information. The more we get the better we can help you.

(1) Give images under metal halide or incandescent (no hps). (better images would help)
(2) Give complete synopsis in one post telling us all the details.

Theres about 10 things that could be wrong on this.. but is looks to be a sativa... if thats the case whatever that tiny pot is theres no way its going to support it to normal growth... get a 10 gallon or bigger for a plant this size. Frankly theres no where near info here to make a good guess at whats going on... what PH is the water going in. and as Curious2Garden pointed out ... whats going on with everything else.....

pot size might be problem, 3 lt right now.
substrate, perlite-coco-humus mix
last feeding pk 13/14, before that 3-4 times 1-2-3 and before that 3-1-4
aprrox. 2 months
temp generally 19-21 C, RH 55-60%, hps 400 watt-30 cm from top,
Ive never checked ppm, water ph is 7.5
I used dolomite lime, before using this soil mix. I think ph fluctuation is very unlikely.
I dont have any test kit, so, I cant tell you exactly what it is.

ph prob and looks like it got overnuted to me