Couple of things here.... first, you need to start cutting back your grow nutes - plants in flower don't need as much nitrogen as they do in veg and that can lead to deficiencies of other nutrients... second, you need to be giving this a LOT more P and K as there are definite signs of a deficiency of both those nutes... you may have a problem with a lockout keeping the P & K from being absorbed and may have to flush to get things back on track .... but I would first start just getting a good PK booster going as soon as possible. I personally use General Hydroponics KoolBloom (NPK 0-10-10) but anything along those lines would be fine. The damaged leaves are not going to repair themselves so don't expect that, but if this solves the problem you won't see those symptoms spreading after a couple of days... if it DOESN'T solve the problem, you'll need to flush.
The dying leaves emanating from the buds themselves concern me (your last photo) and I'm a little fearful this might be some bud rot (but then I'm overly sensitive to this possibility because I lost my entire summer grow to that horrid fungus)... try to pull one of them out... if it comes out easily from the bud, you can try to break/cut the bud open itself to see what might be inside. If you find bud rot, that's an entirely different kettle of fish and will need VERY close monitoring - if you find this, come back here and ask how to deal with it. One of the reasons I'm concerned about this is that your humidity is probably a little too high for this stage... preferably it needs to be in the low 40s... and make sure you've got fans going to keep the air moving around and through the plant.
Good luck....