Thanks ladies. I suppose it's still a tad too early. It's not uncommon for a FET embryo to implant a bit later and start producing detectable hcg a little bit later too. In the fresh transfer that I got a bfp I got a line at 8 dpt (day 2 embryo). With my DS who was a FET, I only got a super faint line at 7 dpt (so 13 dpo) but he was a day 6 embryo, this one is only a day 3 embryo, so I suppose the earliest I could get a line is around 10 days post transfer or 13 dpo which would be Friday. I'm now determined to wait it out until Saturday and then I should know for sure. I think I'll make an appointment to see my FS in the meantime, in case I can just jump straight into another FET. Who knows, maybe I'll transfer the two this time or try growing them to day 5? It's funny because with my last FET which gave us our DS, I probably felt that the FET wasn't going to work because I made an appointment back then to see my FS in case it didn't work to discuss further action, and 4 days before I went and saw him I got a bfp so he just took a BT at my appointment to confirm it.