Like the poster above me said, temps during your period can be really erratic. Highs, lows, drops, peaks, etc. For me, I usually have higher temps until around CD 10 or so. Then they are lower until I O near CD 17-19, then high again.
Here's my chart overlay for comparison:
Notice in the beginning of each cycle my temps are high or erratic. My periods only last around 3-4 days, but my temps are still wacky until around CD 10.