YES! I can't slouch anymore because it feels like my ribs get caught on his legs. The longer I sit up straight, the more my back hurts from the extra weight up front. The only solution is to lay down, and I can't do that as often because I get heartburn.
I have definitely felt some shifting (I'm 20 weeks and some change) I haven't really felt much baby movement, but I feel like my guts are being rearranged. Yay