Couldn't do combined test

[20yomumtobe]

So i went for my 12 week scan today, I thought i would be having the measurements taken for the combined test, however because baby was "upside down" they couldnt get the right angle to get the measurement. They've arranged me another scan next week in the hopes that baby will have turned naturally, however I left without really asking what will happen if it hasn't.
Can anyone shed any light?
Sounds silly, but im a little worried.

This happened with me too. It was too late to arrange another scan because they measured me at 13 weeks. They gave me the quad test a few weeks later which is just a blood test and only gives you a result for Downs. It's not as accurate though. Apparently some trusts offer the NIPT in this situation. I was a little worried, but I now have a very smiley 3 month old, who is very healthy bar a cow's milk allergy.

Each trust will vary. In our region we offer 2 attempts and then if we are still unable to obtain the measurement then we would offer a quadruple test at 16 weeks. As PP said, the quad only screens for T21 but the 20 week scan will look for T13 and T18 so you will still be screened but later on