Thank you very much after reading different blogs and looking it up on Google i feel much better. I just felt really confused! Yes they are sending me for further testing. Thank you for you comment i greatly appreciate it! I will stop stressing now.
Just doing a quick google search, it sounds like you have every reason to believe your baby is fine.
Apparently it is a condition of the renal pelvis (don't know what that is, something related to kidneys) that sometimes comes and goes in pregnancy.
It's a "soft marker" for Down's, which means that often healthy babies have it but it's more prevalent in Down's babies.
Since this is your own symptom, it sounds like you don't have much to worry about.
Are you getting further testing?