I would say bub was ready for a wee.
As a midwife when someone has had something concerning (more then a talipe or low lying placenta etc) on ultrasound its usually followed up very quickly the same day usually. The sonographer would have gone and got the radiographer/radiologist person who is the most qualified in reading and doing scans before they sent you home or referred you to another facility with better technology. If it was serious in the fact it could be fatal or have serious consequences you would know about it already and they wouldn't have suggested you return for a repeat scan in 10weeks.
For your piece of mind and some reassurance can you call your Obstetrician for some phone advise? I am sure he would be happy to analyse the findings for you know instead of you waiting to see him at your next visit.