My first grow -autoflower - indoor

So... things were great in week 7, but I'm also gonna talk about the start of week 8 because I think the plant might be in trouble. Plant kept on growing and developing tops very nicely, getting more tops and them growing better than expected for a first grow. Following a few guides I upped the water supply from around 600-800ml to 1L or a bit more on a daily basis. I'm growing in a tent in a small closed room so i try to vent it at least a few hours a day to keep the humidity at 60% or less. I've continued some minor LST, just on 3 of the smaller outside brances and not too hard. They were still flexible and I assume giving them more room for light and growth would be good. I've noticed for a while the bigger lower leaves are going bad, yellow or dry. one older leaf even just breaking off by touching it. But near the end of week 7 some of the younger leaves on the outside of the plant started to go from nice healthy green to light green and yellow. This is on all sides of the plant on the outside. I was out of town for 3 days while my partner would take care of the plant, but given the color and because the soil was still moist, it was watered just a bit in 3 days. After coming home the soil was still moist and the leaves seemed worse. I waited another 48 hours and just now (almost end of week 8) I've given it about half a liter of water again. The soil was definetly dry now. Given that I don't use fertilizers, there are no big changes in temperature (lowest was 16°C, highest 24°C) or light cycle, I suspect I overwatered her last week. I assumed growing the tops and overall size, it would need more water. It's still too early to notice if cutting back on watering would do helpt, but I definetly hope so. Any comments or advice is welcome. Does this look like overwatering, or another issue to you? Can the plant still be saved or should I remove it, or just not expect too much yield now? I'm a bit worried but also very curious to learn, hoping this will just be a good lesson. Everything has been going so well it would be a shame to see it die just a few weeks from harvest. UPDATE: I put the yellow leaves up as a question and some people pointed out it needs nutrition. One person pointed out that my soil was probably fertilized to start and that will probably have worked out. I had some fertilizer around from my (regular) plants so I used it carefully, hoping to see better leaves in the next few days. I can't reply to questions but if you're one of the people answering: thank you very much for taking a look and sharing your experience!