Do I continue with my NPK?

Hello. This is our 2nd year growing and still so much to be learn. When my plants begin to pre-flower I fed them my 10 10 10 one last time. A couple of the plants at the very top begin to yellow. It’s been 10 days & have only top watered a few plants. The yellowing has not moved, but a few more are turning as well. I know this could be a deficiency or maybe too much on the nitrogen? Can I continue with this feeding schedule & only make it weaker & add some cal mag?