Test on day 10. By then you have a 50/50 chance of a positive coming up positive. Prior to that the negative rate is so high even if you are pregnant that it will mess with your mind. Good luck!!
Hi - I'm not sure what the right date is, but I had a 5 day Frozen Embryo Transfer on 4/13 and tested one week later (yesterday). It was positive! Technically, it shouldn't have really showed up on the HPT yet, but it was an FET, so I had no chance of a false positive and I had some unusual symptoms that I couldn't write off as part of the meds.
If you have a fresh cycle, I think you need to wait longer b/c you can get a false positive from the HCG trigger. The other consideration is how many embryos you transferred and how many took - if you had more than one take then it will show up earlier on an HPT b/c of the doubled hormone levels. Good Luck!