I am 17 DPO and I have already had a positive pregnancy test. I have been continuing to track by BBT and it has been sitting up around 36.70 (98.06) but this morning I had a drop to 36.40 (97.52), this is not below my cover line which is about 36.28 (97.30), is this something to worry about, I am concerned it is an early miscarriage sign, I have no cramping or bleeding at this stage? Has anyone else experienced this?