Low hcg level.what actually happened?

[Polkadotty]

Just had my first round of icsi everything was perfect no problems with egg collection and transfer. We had a perfect blastocyst transferred on day 5. We had 9 days to wait for our first blood test to see if I was pregnant. 7 days after transfer I started to get brown spotting and was devastated knew it was going to be my af. Got my blood test in day 9 and was spotting and my hcg level came bk at only 10. Got to go back for another test in a weeks time. I know it's not going to be raised cos still got af but just confused as to what may have happened. If anyone has any ideas or similar experience would be much appreciated.
Thanks

 

[beneathmywing]

So sorry to hear this! Only thing I am thinking is it maybe was a chemical pregnancy?

 

[BethK]

So sorry, did you have a positive hpt?

 

[Polkadotty]

I've not done hpt. Due another blood test on Monday.