Keto diet not achieving ketosis

When I tried the Keto diet, I was eating a ton of zero-carb meats. We call that hog heaven where I come from. Anyway, I was well under 20 carbs per day, but never got into ketosis. What the Heck, right? In my confusion I did some reading and discovered that our amazing bodies turn excess protein into glucose. I'd never heard that before.

So the trick with Keto is limiting your protein (to a degree) and ramping up your fat intake. Unfortunately, that means you're still limited on the amount of food you can eat in a day, and that realization killed the only reason I ever considered a Keto diet

Your liver can only hold so many carbs, and it'll be used up in about 2 days of average daily brain activity even - so that's not source of extra.
Muscle glucose stores can't be put back into the bloodstream - so that's not source.

High levels of protein that go unused by the body as amino acids will be converted to glucose - so that could be it.
At a certain point with enough protein, or way too low calories, body can decide conversion and having glucose is more important than other things the amino acids could be used on.
That includes the daily breakdown of muscle that occurs somewhere, body could decide the diet is too extreme and it just won't build that muscle back up with available resources - if there are even any. That's a really bad state to be in.

Or your test of being in ketosis isn't accurate and you are really.

Do you recall going through a slight tired brain fuzzy day, perhaps with a headache?

And how are you confirming the carbs - you logging everything by weight in MFP?

How many overall calories have you been hitting, and how much of a deficit does that appear to be, how much weight loss rate is it?

Are you doing a lot of fiber that you aren't counting? because some actually is absorbed depending on type, usually not meaningful amount though.