My bbt was elevated for almost a week when it suddenly dropped but I started my period and now am late Could still be pregnant or is too since the drop in temperature?

It is unlikely that you are still pregnant if your basal body temperature (BBT) dropped and you started your period, as these are usually signs that ovulation has not occurred and pregnancy has not been achieved. However, if you are concerned about the possibility of pregnancy, it is best to take a pregnancy test to confirm.