Thanks guys. Im still not 'sure' if its a boy or girl, but I think its a boy based on the sonographers educated guess. We dont want another scan at this stage because it is kind of 'fun' not really knowing.

We found out our first DS was a boy at 19 weeks and there was never any doubt of this at any one of the 4 scans I had. The sonographers (and my Obs) were always sure and showed me the appropriate 'evidence' then (Ie the view from underneath). I suppose I just expected this time to be the same. I thought it should be pretty obvious if it is a boy, but apparently not. I never knew that they got it wrong so many times.