Implantation question

I've been tracking bbt and I'm 8DPO today. Yesterday I experienced what I thought was an implantation dip due to the fall in temperature. Well this morning I woke up with period-like cramps that kept me up for an hour or two (2:30-3:30am). I then took my temp when I woke back up and it was back up again. I'm confused if the cramps may have been implantation since the temp dip was yesterday morning. Anyone have any ideas or advice? AF not due until this weekend (three apps have different dates for AF 18/19/20). Any ideas?