2nd Guessing

I got a counter offer back on the house last night, and I'm not sure what I'm going to do next. Well I am going to counter, but I'm not sure how much. But that isn't really what has me questioning this move. I'm starting to wonder how I'm going to fill up a house that big. While I feel like I am bursting out of my current place I don't think I'm ready to go into something three times the size. Ahhh, lets be honest here, I wouldn't be myself if I wasn't second guessing.