Quad test

[lisaBaby1]

I'm 21 weeks pregnant & not had any screening test, although we asked to have the quad test.
We decided to go for the bloods test/quad test which was booked with the hospital booking bloods test, but the hospital only took the booking bloods test and missed out quad test.
I heard nothing back and only found out they forgot to do the quad test when I enquired with a midwife at the hospital after my 20 weeks scan.

This is all new to me, as it's our first baby and I don't know what's been done & what hasn't! It's not my job to check for them, although I have constantly checked all my appointments have been booked & attended on time & it clearly states in my notes they were to do the quad blood test with the booking blood test.
I'm pretty upset the hospital has mucked up again (I've had issues with them since I joined for antenatal!)
Their answer is if you don't like the service go elsewhere!

Although everything shows normal & fine at my 20 weeks scan, we still wanted to have the quad blood test just to be sure.
My hospital midwife is not back in work for another week. However, I am seeing my local midwife this weekend.

At 21 weeks pregnant, isn't it too late to have a quad test and check for any birth defects or genetic diseases like downs syndrome?