Just out of interest, I am not pg or anything?
My DH and I had conversations about names when I was pg with my DD (didn't know we were expecting a girl) and loads of names we liked the shortened version of but not the whole name - Charlie but not Charles etc.
A colleague was horrified that my friend had called her son Jake rather than Jacob and wouldn't accept that I thought it would be strange to give a child a name you really disliked for the sake of the nn that you did.