Nutrient burn or nutrient deficiency?

That leaf in your hand was off the lower bottom portion of your plant? The first pic looks exactly like nitrogen deficiency. Uniform leaf yellowing from the tips back and a curling crisp up. I also see some potassium issues in the 3rd pic. Flowering plants use a ton of potassium. Usually most nutrients on the market are formulated for growing Weed. So long as you follow the feed program and maintain your pH you shouldn't have deficiencies. Where deficiencies come into play is when you have a pH issue or a soil toxicity issue. If through the plants life you've never flushed your soil out, then it's likely in need of it. I usually flush my soil before going into flower. Just to reset it and ensure proper pH water has totally flooded my soil. Then i let it dry out, then begin flower feeding.