It's about the right time for an implantation dip.
Disturbances during the night will affect your temps but they will usually cause the temp to be up a bit, not to dip.
Implantation occurs most often between 6-10dpo so you'd be right in the timeframe.
Good luck for your October bub! Libran's rock (DS and I are both Librans so I'm a bit biased )