What is the earliest doctors can confirm it is not an ectopic pregnancy?

Carolina • 1 fresh successful cycle 2015 ! 15 month daughter via IVF and going thru FET Aug 2017 🙏🏼🙏🏼 1 embryo ready for transfer!
I had an ectopic back in January!  So scared of another one. I might be pregnant now! Just a couple of weeks along, and a couple of weeks before my scheduled <a href="https://glowing.com/glow-fertility-program">IVF</a> ! How soon can we find out if we are in the clear?