PLS help! I think I'm in trouble

OK, so this is my first plant and I know it stretched really bad, but as far as the plant health is concerned it's been perfect until about a week and a half ago. I added some 1-10-0.2 guano to the soil AND mixed some in with my water. I'm assuming this is the cause of my problems.

I've flushed 2 times so far and its getting worse not better. I should have taken off the top layer first but I didn't. Lots of noob mistakes here. Now the leaves are curling and turning brown/black and falling apart. It started with the oldest, largest fan leaves and has now spread its way outward to the leaves directly around and even under(!) the buds.

FYI this is a Chocolope and I've used T-5's to veg it and now some 2700K CFLs added for the red spectrum. As its my 1st grow I didn't want to invest too much right away, though I regret not doing so now. I flipped to 12/12 on October 9th, Choco's take 73 days to flower to I plan to harvest around the 21st of December.

What I need to know is, Am I fucked? And if so, How fucked? Will flushing fix this?

And also, worst case: Can anything be salvaged from this plant if it's gonna die? The buds look nice though small, but have 1/4 - 1/3 red hairs, and there are plenty of trichomes. No brown hints in them yet though.

Here's some pictures, Thanks in advance for the help. If it wasn't for forums like this I'd be in much more trouble.

just taking another look at the pictures I posted, it's worse than it shows in these pictures but you can get an idea, especially from the last one. THANKS!

Flushing washes away the nutrients that the plant needs to grow and is usually bad for the plant. When you're sure that the plant is burnt and its lowest leaf tips are turning brown then you still only want to flush lightly, lowering fertilizer levels without eliminating them. Afaik there is never a time when you should flush twice in a row.

Your plants don't seem to show any signs of fertilizer burn. If a problem started when you gave them Guano, then it's either a Ph issue or overwatering. Check the soil's Ph and make sure to let the soil dry well between waterings. Also, you should really give it a good all-around fertilizer mix (Ph adjusted) as soon as they're ready for water and after you check the soil Ph.

Would I not want to flush more than twice in a row for the last two weeks? Like, before I harvest?

also I'm assuming my plant is locked out and no longer taking in nutrients. How can I fix that? Lower the Ph?

No. Never flush twice in a row. Even at the end of flowering, flushing twice or too soon can cause the plant to stall out and simply stop maturing altogether until you give it some food. When plants stall at the end of flowering, you have to give them more fertilizer to start the budding process again which causes fresh bud growth to appear that won't have time to mature. The buds can end up with tips that give a speedy high while the rest is fully matured.

You say that you're assuming the plants are no longer taking in nutrients- have you given them any since flushing?