New grower who needs help diagnosing plant issue

Hey I’m a new grower and started noticing issues with my leaves just over a week ago.
I’m on week 6 of my indoor grow.
I’m using about 50% coco 25% soil with myco fungi and 25% perlite in it (approximately not exact) in 5 gallon fabric pots.
I’ve been using advanced nutrients ph perfect Micro, Grow, Bloom about 4ml of each per L of water at this stage. It’s makes my water about 6.5ph and it’s about 850 ppm. Planning to use Advanced nutrients big bud starting week 2 of flowering. Water 1L every other day now.
It’s a purple hulk auto flower with a 20/4 light schedule.
Humidity is 40-45% low temp is 16C usually temp is 20-23c. I’ve read that autoflowers actually can withstand cold temperatures a lot better then photo periods so I haven’t been too worried about it going to down to 16c
My issue is that my leaves have holes and some discolouration. On one of the pictures there’s this orange coloured hole and I’m not sure if it’s nutrient burn, disease or even light burn and was hoping someone with more experience can help me diagnose it so I can treat it. I don’t think it’s pests as I used the sticky tape and haven’t caught anything and also put a white price of paper underneath and flicked the plant to see if any specs fell on it and haven’t found anything. If you know or got an idea let me know. Thanks in advance!

Do you have a cat?

I do actually

Kinda looks like the response of some of my plants to a too strong dose of Humic acid and Kelp....
I see the beginning of tip burn to verify the possibility.
But those spots of damage..... are you quite sure you didn't have a rampaging moth in the grow for a day or two, or some such?
I would run a bit of water through them to see if the twisting of the leaves goes away in the new growth, and that would tell me to lighten up on my nutes, because they are getting to much humic acid and kelp (which is in the nutrients)-
The Virginia 5/2 ratio for humic acid and kelp is a bit much for some light feeding strains, though it seems to be like nitrous at first.
The plants will start acting squirrely (twisting of leaves and splotchyness) and begin to burn up as it processes the kelp.
This could also be a result of deficiencies beginning because of your PH. Crank it down to 6.0 and see if it helps.
That's all I got.