Pregnate? Or Sick?

Question
I am not exactly sure how old my bunny, Smithers, is but she has been weaned from her mother, and is eating solid food, so my guess is 2-4 months. I bought her from a SMALL cage with a whole lot of male and female bunnies. I noticed that her lower belly is pretty big. It sort of firm, but It doesnt feel as if anything is in there, but I just smoothed my hand over, I didnt push. she isnt very moody, and she lets you pet her, but she wont be picked up. She is very passive and mostly sits there, and doesnt do anything. she has built a sitting area, but I dont think its a nest. I hope you can help me.
               ~Smithers

Answer
A nest will be packed tightly and have a smaller hole type place where she will have babies. Close to birth she will pull hair and line the nest with it.
www.islandgems.net/palpating.html is a good website with a description to do what rabbit breeders call palpation. Which is a pregnancy check. If all else fails you could always take her to the vet to get her checked. Likely what you are seeing though is pot belly= a harmless condition seen often in young just weaned rabbits. No big deal, it will go away with age.