1st Time PC Stealth Grow CFL

Okay so this is the first time I've ever posted on this forum, but I've visited it multiple times when looking at other people's journals for tips for my grow. I am growing in a PC grow box because this is my first time growing and I wanted to experiment before getting bigger. Also space and stealth is somewhat of an issue so it was perfect to try and grow in the PC grow box for now. I am growing Dinafem Cheese Autoflower in my already made PC grow box. I'm currently on day 20 since the seed has sprouted. I'm growing in Fox Farm Ocean Forest medium. I haven't started to use any nutes yet since the medium has enough for now. I have the Fox Farm Trio for nutes and I'm going to start using them once I'm 1 or 2 weeks into flowering. I'm not sure if my plant is in veg or flowering because it has been 20 days since sprout and I've started seeing small pistils and such forming at bud sites, so flowering may have just began. I'm using 3 6500k CFL bulbs along with 1 2700k CFL bulb, each 23w, for the veg period. I want to know if I should switch to 1 6500k CFL bulb and 3 2700k CFL bulb for the flowering period, but I'm not sure if flowering has started yet.

I've been having some problems with my plant and I've attached pics for you guys to see. On two different individual leaves, the leaf has curled along the side and is brown along that side. Also some leaves have small yellow spots on them. Some leaves also have yellow/brown tips that may have been caused by heat. I was thinking this may have been caused by a little overwatering from before because this hasn't spread to other leaves and such. I think so far my plant is growing pretty well, but I want to avoid future problems, so I want your guys opinions.

My PC grow box temperature goes up to around 82° and during the night it goes down to around 68°. I'm running on a 20/4 schedule. My humidity stays around the mid 20% and I can't get it to go up. Would anyone know anyway to raise it to around the 30-40% mark? I've tested my pH of the runoff water and it was around 7.0, but I think that is inaccurate because it was measured using a moisture meter with a built in pH meter. I need to buy a good, cheap pH kit for testing and adjusting the pH, so if you guys can recommend me one, I'd appreciate it. I plan on LST'ing my plant as I've already pre-drilled the holes into the pot. I was wondering how much water you guys would suggest for a one gallon pot because that is what I'm using. I feel like I'm overwatering even though I'm only using around 12 oz or so each time I water, which is once every 3 days or when my the soil feels dry with my finger. My plant also has started to develop a slight distinguishable odor to it, but when it starts to smell more, I will open my ONA odor gel. Please leave any opinions or recommendations below as I need all the help I can get! I've attached multiple pics for you guys to see my status right now. These pics are from yesterday. I will add a new entry to the journal for today! Thanks for reading!

DAY 21:
I think flowering has began. I've started to see small pistils form at the bud sites and around the lower part of the plant. Please provide your opinions on what you think is causing some of the yellowing on the leaves. The temperature is around 79° and humidity is about 30%. It may be due to overwatering, so I will limit how much I water the plant, so I can eliminate this issue. Thanks!

Can someone help me with a problem that is starting? My lower leaves are slowly turning yellow and starting to die. I don't know what I'm doing wrong or what nutrient deficiency there is. I'm growing in Fox Farm Ocean Forest, so I thought that nutes should be enough until flower period considering I'm growing an autoflower. Someone please hint to what I'm doing wrong!

Bumping this up so I can get a reply to my problem. I've switched the lights to 2700k for the flowering, but the bottom leaves are still yellowing. Someone please advise me what to do. Should I start using my nutes to fix my plant?