Thank you so much for taking the time to post the pics, Sugar is so adorable!! I'm not sure what size my bag is, it measures 13x9x7 and is supposed to be good for dogs up to 8 lbs. Gypsy weighs 4 1/2 lbs. and measures 8" at the shoulder and 9" from base of neck to base of tail. As you can see from the pics she looks bigger beside it than Sugar does but really when she lays out flat and puts her head on the rest she doesn't seem to be crowded and she can stand up easily and stick her head out. She doesn't seem to mind it at all so I think I'll keep it, I just absolutely love it and can't wait to use it on our road trip in August. She'll never have to be stuck in it for any length of time, it's mostly for places where she can't walk (like in crowds) or for when she gets tired of walking. What do you think? And thanks again for your help.
ps. please excuse her scruffy appearance, it's bath day today.