As soon as the embryo/blastocyst hatches and buries into the lining of the womb that is when your body starts to produce the pregnancy hormone which shows up onthe preg tests.
I think therefore that day 10 may be a little early but I think it all depends on your body and how much Hcg it will produce. Some pregnancy tests are very sentive and will pick it up but its up to you whether you want to do it that soon.
I have said on here previously that I will be testing from day 10 but the more I think about it and the more I have read that you can get false negatives/positives and they are really unreliable, I may just leave it until 1 or two days before my actual blood test.
From your dates that you have given it sounds like you had blastocyst transfer so it may be that your body will be producing the pregnancy hormone by Tuesday or Wednesday this week!!
Its up to you but I would suggest you try and stay calm (easier said than done I know
), be positive as your embryos actually "made it" to blastocyst and leave the testing as long as you can..................if you read other stories on here a lot of the ladies say don't touch the HPT's at all and say to leave the testing to the dr's. For me though, I think I will be testing to have some idea what to expect on the DDAY.
Hope this helps you make your own decision but remember a negative can become a positive and (taking into account the final injections etc) a positive can also become a negative..................its hard I know.
I see you are on the list with me for the March testers - and I will be looking out for that BFP
for you.......x Goodluck