Hi Kara. 2 scans is the norm in most areas - it may just be your trust - I imagine they would have explained any concerns/reasons for providing you with extra concerns though so I wouldn't worry. I'd just be pleased at getting to see more views of baby!
We have one DS but no gender preference here either. On the one hand a girl might be nice as we only intend to have two, on the other, I have all the clothes etc for a boy and I think it would be lovely for DS - a great buddy, which I would love. Didn't find out first time round - more inclined to find out this time but will decide on day.
Can't remember who mentioned the dangling appendages but I have it from a sonographer that that's not what to look for at a 20 week scan. Don't want to say what you do look for in case some people don't want to know. That said, even armed with that knowledge last time I had no clue - baby spent so much time moving around.