My fitbit one confuses me - active minutes? floors?

Francl27

I got a fitbit one last week and I like it, but I'm very confused about the results it gives me.

First, floors. I went to the basement and second floor twice in one hour the other day, and it only counted as 2 floors. I went for a walk in the neighborhood the other day (there are some hills) and it counted as 4 floors. Yet today on my treadmill at the gym I had the hill setting with a lot of 4+% hills, and it still shows only 4 floors for the day. How in the world does it work?

Then, very active minutes. Yesterday I did an hour walk in my neighborhood and one hour of les mills pump (which I know doesn't register well as I'm not moving), and I had a grand total of 5 very active minutes for the day. Today, one hour on the treadmill at 3.5mph (so maybe just a little faster than my walks) and hills, and it says 1h and 5 minutes of very active minutes. I'm very confused.

Can anyone help me? It's not a huge deal really, I'm just trying to figure it out...