My First Grow

Week 10 Day 64 (9/18) Doing good, really starting to see some frost form up. Waiting for her to dry out a bit so I can give her some cal-mag. I've read that autos tend to go heavy on the cal-mag, and using RO water doesn't help the situation. Day 65 (9/19) I gave her some water last night and added in some cal-mag. She seemed deficient so I went with 4ml in about 3/4 of a gal of water. She has a handful of lower leaves that are really yellowed up and the magnesium deficiency was getting worse. Hoping that it will go away with the cal-mag, though I'll probably give her some more with her next feeding. Day 66 (9/20) Her upper leaves are still noticeably more yellow than lower leaves. I'll do some research and try to figure out what is up. I doubt it is light burn, as I'm only using an HLG100 at about 12" from her tallest point. EDIT: just kidding, it may very well be light burn. I'll lift the lights up a bit. Day 67 (9/21) To combat the possible light burn, I raised my light up a few inches. Unfortunately, if it worsens I'll have to figure something out as I'm now at my height limit with the current setup. I could get a few more inches by finagling with the light hangers. Pistils are starting to brown on several buds, so hoping that is due to their ripening rather than something going on with nutrients. She'll probably be needing fed again in a day or two. Day 68 (9/22) Another day, another....whatever. She's still going, but still seeing some yellowing on her upper leaves. I'm hoping with her next feeding it will help her out, but I may have to pull her out and get some good pics and ask around some forums. They usually help me out, if anything they help ease my mind. Day 69 (9/23) I fed her this morning. Pretty much the same stuff as last feeding, but doubled the shooting powder (2.6g -> 5.2g) and went a little heavier on the Cal-Mag (5mL). I'm still seeing damage on the upper leaves, but can't tell if it's progressing or staying the same. I had her pulled out this morning for feeding and completely forgot to take pics to post and ask about her health status. Her pistils are browning up, so I think she is getting closer. I just have no idea when to start a flush. I'll whip out the microscope tonight and take a look just to see if I can actually see anything. Might have to invest in a better microscope. Day 70 (9/24) Finally got some good pics of her in normal light and asked around the forums I haunt. Consensus is that I have been overfeeding her and have caused a nutrient lockout. I messed up by feeding her with every watering, which I started doing when she was showing deficiencies with feeding on every other. Also one person said I shouldn't be feeding at full strength, but I feel that she has been at full strength for quite a while and it has been only recently that these issues have shown up. Idk though, being my first time I really don't trust my own rationality. It was recommended to use a TDS meter and do a flush to bring down the ppm. BUT I don't have a TDS meter. They didn't elaborate on how to go about correcting this without a TDS meter and monitoring the ppm, but they recommended not doing a flush. So I have no idea how to proceed at the moment. I'm thinking I may flush, and follow it up with a feeding a few days later. If I do, it might be the last feeding I do as I'll be starting week 11 tomorrow. Most of the Barney's Farm Zkittlez OG diaries I have seen go to about week 12, and I'm assuming mine will go to that at least. If I hear more feedback about my problem, I'll update.