
It looks very much like it
could be a fallback rise. I have one just about every single cycle. My temp will shoot up the day after O, then drop back down the next day only to recover and remain high for the remainder of my cycle until around CD 11 or so.
Go ahead... take a look through my charts and you'll see. (I hid my FF link in my little balloon ticker thingie) It's a perfectly normal shift pattern.