woohoo for toilets :D
Diege implantation can result in a dip of 0.3 degrees or even below Coverline, but it must soar back up the next day.
How many dpo are you? It normally occurs between 5-10dpo, depending on how long your LP is.
It's not a reliable indicator of pg, as you can get a dip without being pg, but many women who do chart and get pg can clearly see the implantation dip around one week post ovulation.
The best indicator for pg using temps is a triphashic chart. 18 high temps above Coverline will also indicate pg (but I never waited that long before poas!)
All my charted pg have shown this.
Rather than an implantation dip, I get a second tier of temps higher than the first 6 temps post ovulation.
example
I do not use the site linked, I just googled it 