Really awful "claw" leaves

Hi everyone! I'm new here, been lurking around reading for a while. I've tried a few things I've seen as solutions to this but still can't get rid of my problem.

I have one plant under 160w of led lights, in a 15L pot with soil, temperature is around 20 Cº during daytime and 15 Cº at night, humidity 60%. First week of flower.

Past sunday I've noticed two young top leaves were curling really bad, in the form of a claw, and they felt rusty. After a quick search online I've found it could be nitrogen toxicity. I've fertilized with NPK once, having done a transplant to fresh new "hot" soil a week ago, so that could be it.
On monday I flushed it with filtered water, but now it's friday and it's even worse, with two new pair of leaves curling, in addition to the other pair that remains the same.

I wonder what could it be? The day I did the flushing, when I finished, I've added a small dose (25% of the recommended by the manufacturer) of micro nutes, in 500ml water. Its components are:
Fe: 2,5% Mn: 3,2% Zn: 2,6% B: 0,7% N: 1,1% C: 7,2%
The thing I'm concerned about is that the PH of this fertilizer is 4.1. I want to bring it up now (didn't realize at the moment) but the soil is still really wet because of the flushing. Should I water a little or it isn't recommended? Or could I do foliar feeding while the soil dries up? Thanks in advance to all of you.

Pics:

pH your water after you've added your nutes to it. Check your runoff pH.

Try to raise your temps and bring down humidity to around 45.

Thanks! Can I give her some silice by spraying the leaves in the meanwhile? The soil is still wet so I can't correct the pH, and I've heard silice is good for stress and temps variation. This indoor is actually kind of outdoors, greenhouse sort of thing, and I can't control the cold. It's autumn here.

Thanks for the tips! It's my first grow and I feel really crappy when the plant looks so sad