Thanks for all your responses, it's reassured me a bit. I've got the anomaly scan in a few weeks so I'll try not to stress about it.
@bubblybrit Harmony test is too expensive, otherwise I'd probably go for it. By additional screening I meant scans, so possibly I will be offered them later in pregnancy?
@welshweasel I'm wondering if maybe they will just wait to mention it until later as they can't do anything at the moment about it, but may effect me later on.
@maxiflump1 I'm in my late 20s, so higher odds than it should be given my age. 
@Fredthespider yeah, that's what I'm thinking, that they will make a bigger deal of it later in pregnancy, but at the moment there is nothing to do as it wasn't low enough to make me high risk. My NT measurement was 1.6, so nothing unusual there.
@LookingAtTheStars89 when I got the NT combined test results, there was a letter that said I was low risk and a printout that listed my PAPP A and HcG levels, info about me, and the NT measurement. Then it gave the odds as calculated by the combined test for each.