Congratulations tranquility 
Oh feeling, I felt just the same with DS. I was on my own when I went for the 20 wk scan, and I was sobbing so hard when I left that the sonographers called the MW to get her to check on me
. These feelings are nothing to be ashamed of- there is a difference, and when I found out it was a boy this time around as well, I wasn't as cut up as before, but I did feel very weary at the thought of years spent chasing another little whirlwind around....I don't naturally like physical activity or sport!
But, you know, DS is wonderful- so affectionate and loving (when he's not being an arsey, oppositional little sod- but that's not gender specific
) and quirky and intelligent...and I think -"what does his sex matter weighed against the fact that he's a lovely little person?" So, to get another one like him is not going to be a hardship.
I do feel weary at the prospect of more chasing- but not all boys are incredibly active OK, most are, and some girls are handfuls too....I was somewhat mollified, at DS's party, to notice 2 of the children escaping together- apparently trying to make it back to the village on their own- until they were mere dots in the distance, and one of their mums had to sprint after them........yep, they were girls
.
Do you already have a DS? I'm also cheering myself up with the thought that room sharing's going to be easier.....