Has the battery in anyone's thermometer gone flat before? And how did you know it was going flat? I've actually misplaced my bbt thermometer so just been using normal digital one in the mean time but last month or so the temps seem to be just super low, even dh so its not just me! FWIW As I'm still bfing I don't know how accurate temping is gonna be but was fine after all other babies, I'm just really wanting to keep an eye on whats goin down there so as to know when to expect af... Or bfp of course