Nitrogen deficiency

So I believe I’ve had nitrogen deficiency all the way up into week 7 of flower before I realized why my leaves were turning yellow before my flush so question here is can it kill off random buds because I’ll go check on my plants and randomly will have buds dying off and it doesnt look like pm or any type of mildew and Ive noticed the buds that do die off will have yellowing leaves first even sugar leaves then the whole buds eventually dies off after the leaves but like I said the bud will be perfectly fine just over dried because of course it’s under the grow light until I find it and cut it off can someone tell me what’s up here it has happened before too in some of my other harvests btw I did try cal mag and it seemed to slow down yellowing