PLEASE SAVE MY PLANT! Blue Diesel (Blueberry X Sour Diesel) LOWER LEAVES DYING

Hi all, this is my first grow as well as my first post here on rollitup.org

I'm experiencing a problem with my lower leaves that's left me confused.

I over-watered the plant 2 nights ago, and I think this might've knocked it's nutrients out.
I've added guano and bat blood as flowering fertilizers - I'm sure it is either in pre-flower/flowering .

Also, in the third picture, you can see a discoloration of the lower part of the stem. Is this normal as it ages? Or did I leave it too moist?

Could it be a sign of mold/fungus?

Is it a sign of deficiency?
Over-watering+Loss of nutrients?

The second picture is an aerial shot of it, the tops look fine, except for the bottom!

The pics don't look as bad as they look IRL, the pictures aren't detailed as I'd wish - but you could get a general idea(I hope) of what I'm referring to.

She looks so heart-broken, I don't know why this is happening and if it's normal or not.
Please help! Thanks in advanced and looking forward to discussing with this community!

What kind of light are you using ? The bottoms of the plants arent getting enough light and are starting to die. Not really that big of a deal the discoloration of the stem is normal also. Kind of brown and rough like a young tree lmao

check it very closely for mites

and back off nutes for couple weeks then start slow again

what are your temps?

alot of people mistake crusty brown tips for nute burn. Its not nute burn but usuallt K def. Yellowing is N defiency so Id say add some N as long as your ph and everything is good. If you notice the leaves with crusy brown tips have some yellowing too, that means defiency. A burn does not yellow before it spreads, it just burns up the green.

mine was starting to look like that bcuz of under feeding n heat stress do u test your ph? temp? what lights are u using?