You’re almost there!
Remember that a clear pool can have nascent algae consuming your chlorine. (Which I suspect was your case all along) That’s why there’s 3 end of slam/need to slam criteria not just basing things on how it looks. There are many clear pools/ clear water that isn’t sanitary.
I know this sucks but a 2 day slam with a clear pool is a whole lot easier than trying to clean up a green swamp. If you hadn’t of been supplementing & running your swg too you would’ve already had one, it was only a matter of time.
Let’s pass the
Overnight Chlorine Loss Test to be certain you’re in the clear & can start your trouble free pool life!
For tonight try this to be as consistent & accurate as possible:
Do your last dose of the day then let it circulate 30 minutes or so before getting your sample for the oclt. It’s possible last night it just wasn’t mixed quite all the way.
If you’re not exactly at slam level that’s fine. Then when doing the tests try to stick to uniform drops

(don’t squeeze the bottle, let them come out) about a drop per second (this also makes it easier for counting cuz there’s a rhythm). No long pauses between drops. Immediately write down your number of drops or say it out loud. Then do the math after.
Do the same things the same way in the am.
I suspect you really passed last night but its easy to lose track when counting all those drops!
I count the drops just like I count money. I say the 10’s louder so I don’t lose track of where I am & I repeat my final number so it sticks in my brain. Then I walk around saying the final number until I do the math & record it - my family thinks I’m crazy

but they enjoy their clear clean pool so they don’t give me too much trouble with it.