PH fluctuation. Start there and trouble shoot, most of the time its a little problem something out of whack, and not a plant illness or disorder. Keep our parsmeters in check and youll have healthy plants. Oh ya and dont worry so much youll be fine.
looks like you over nuted on nitrogen an am locking up other nutes..like i said flush with phed water...water with ph'd water for a week...then re-feed ph'd nutes at half dose then continue regular feedings n waterings...should be clear peace az