Really hope this is normal.... pics

5 ft tall just over 5 week into flowering 100% sativa and it started with 2 at a time bur now most of the bottom quarter is yellowing and, i know they lose some during the flowering stage, does this sound about right, also the fan old fan leafs 3 ft up are starting to droop badly, is this all normal
TiA

Any experienced growers out there tonight?

leaves yellow and fall off during flowering... but looks like you have nute burn..

Ok thanks im gonna give her a feed

Don't think it can be nute burn kali, the leafs just go yellow over about 3 days, then look dead, that brown shit on the leafs happened as the leafs were decaying, the 3 seats of leafs have diead one after the other over about 3 days, but she is a big plant, im hoping this is just sheding her old fan leafs, she almost 6 week into flowering, also its only the fan leafs the bud stems seem fine apart from the odd little fan leaf falling off of them. The pic is about 2 week old but ive circled the area affected, how much do plants shed norm during flowering?

The pic i meant to add..

i wouldn't sweat it.

personally, i'd as twisty said, mix in some extra veg nutes into my feed.

good looking plant by the way..

It looks like a similar nute burn I had, which I suspect is too much phosphate. You might bump up the N as suggested.