Deficiency or nutrition burn?

Is this a deficiency starting or is it nute burn? As of right now its just a few leaves at the bottom.

It looks as though the plant has started flowering…It is normal for older bottom leaves to start dying off as the plant ages and starts to flower.

Great. Thank you! And yes by my count im in the 4th week of flower. I just didnt want to miss something and it start spreading like crazy.