Hi just got my first thermometer and opk's used an opk before and there were two lines the test line not as dark so take this as a neg as when searching the internet it says that it has to be as dark or darker to be a positive. I am cd12. Took my temp today for the first time so probably not going to know how it compares as right in the middle of my clycle. When I took it this morning it was 36.1 and now it is 36.4. Is your temp suppose to change through out the day?