Am really confused with my BBTs at the moment-I'm in my 2ww and as normal am waking up like clockwork at 3am take my bbt and it's high around 36.8 but then when I take it at wake up time at 6:30 it's dropped to about 36.65/7. In previous months I have adjusted it at 3am and taken it again at wake up and it's been spot on. I'm confused now at what temp I should be recording?