Temp dropped at 6 or 7 DPO ??HELLP

Laura • I`m 28yrs old , I`m a stepmom to an amazing 4yr old boy Levi. Just started BC pill 1st time ever to get my hormones and body evened out.
What would this mean i thought it stayed high til u start your period 
What's does this mean can anyone help me WHY DID I HAVE A SUCH. A DROP OF TEMP AND WHY AT 6dpo someone help me out here ladies please... I wanna know why this is happening