BBT dip sign of implantation?

Kristen • 29 years old and a married mom of three, 12 year old son, 3 year old and 1 year old daughters! I am a breastfeeding, babywearing, bedsharing mama! 😂
I had I pretty significant BBT dip today. 4 or 5 dpo. Could that be implantation or is it too early?