Yup I am a rocky road person. If you are a light sleeper it kinda takes you in and out of deep sleep and thus out of the lower bbt range. Maybe something is making you toss n turn, or you are dreaming excessive?? Anything that causes the mind to come out of deep sleed can cause it. Or fans, more covers, less covers, someone sleeping beside you being restless...any of those kind of things.
Good part is your post O looks great!