Dip in orange and high in red?!

So at 2G class this morning I (39, F) got a weird result: a dip in orange and high in red.

Gray: 4 Blue: 12 Green: 16 Orange: 6 (!!!) Red: 20 (!!!!) Cal: 624, splat: 26

What does it mean, what did I do wrong?

Result from a few days ago as a reference: Gray: 4 Blue: 13 Green: 16 Orange: 16 Red: 7 Cal: 597, splat: 23

I power walked at both, and the classes are the usual 2G; nothing remarkably different. Usually I had a banana or an apple before workout, but this morning I skipped it. I don’t think that would make a huge difference but thought I’d mention it.

Thank you :)