Nur on "When does your clinic do first Beta?"

Hi
I have cycled many times. In the past, my previous clinics did the beta test 2 weeks past the transfer....regardless if it was a 4 or 5 days transfer. My current clinic tests 2 weeks after retrieval. since I just had a day 5 transfer that means only 9 days after the transfer! I am wondering what is more commom and why each is done? I am a bit worried that since I always was tested 2 weeks after transfer, maybe 2 weeks after retreival will miss a late implantation?
Nur