Ok so I need some insight/advice ladies

So I temp my bbt every night.. I usually wake up in the middle of the night, take my temp and then take it again at 6:30am when I wake up for my day. I usually wake up around 2 or so, then go back to bed.

Last night I went to bed at 10:30.. woke up at 3am (so that’s a 4 and a half hour sleep) took my temp and it was 36.54

Went back to sleep, and woke up at 5:45am, took my temp and it was 36.35???

Waited a few minutes, and I felt hot so I took my temp again and it was 36.58 lol

I’m in my luteal phase so... I don’t understand.

And I’ve never had it lower than my temp in the middle of the night like this during my luteal phase lol. Usually a lot higher.

Which reading is more accurate???

Would a low battery be the cause?

I just want to know which reading to use as well.