Hi & welcome to BB

The average couple with no fertility issues takes around 12 months to conceive. Some longer, some shorter but something like 85-90% of couples will be pregnant by 12 months actively TTC. This is the reason why doctors won't do any testing for infertility until you've been TTC for 12 months unless there is a previously known about issue.

Implantation can occur from 7-10DPO so 9DPO isn't unheard of. During your LP the hormones that are released are what causes your temp to increase so it would be unusual as a general rule for your temps to trend downward during your LP.