I put on about 18kg with DS, I just put it on right from the beginning.With this pregnancy I haven't put on anything yet, might be because I am also breastfeeding.Everyone is different though, as long as your healthy and feel good I wouldn't be concerned.

As for the movement, don't worry about that at all! I felt DS for the first time at 16w6d(just to be exact!)Haven't felt it move with this one yet, but I'm hoping to feel it slightly earlier than last time.