I am on CD5 and have decided to start charting my BBT. I bought the thermometer when AF arrived at the weekend. I did it for the first time at 6 this morning and it was 36.85 degrees. Is that a bit high? I also have really light periods and went 4 months last year without getting one. all tests have come back ok. I just want to have plenty of information if I end up having to see a doctor. Would really appreciate any tips/advice.