BBT help please!

So I took my bbt this morning for the first time, and I took it very first thing before getting out of bed. Got a temp of 36.5(Celsius)

I was curious to see what the difference would be after I got up and moved around a bit, when I took it again it had gone down to 36.3. Is that normal? I thought it would go up once you started moving.

I'm just trying to figure out what's typical for those days I forget or do it late, so I don't freak out.