Peggy IL
I don't think it would hurt to call. I don't know too much about the Southside Animal Shelter, but I'm guessing that they probably only check up on emails a few times a day??
I do believe that they are a no-kill shelter, although I'm not positive about that. In my experience with shelters (how we found our baby), most times they will not "hold" a pup for someone. Unfortunately its kinda first-come first-served. We ended up driving to a shelter 2-1/2 hours from where we live and called every 15 minutes to check and see if Ruby was still there (and got lucky)!
I say call! That way you will know 1) if she's still there 2) if there's an application that you can fill out & 3) pending the approval of your application, if they will hold her so that you can make the trip.
I'm rooting for you--much better for Amber to find a family that knows about this great resource and is willing to learn, than someone who walks in to the shelter and sees a cute little puppy and hasn't done any research (prolly how she ended up there in the first place--at only 10 weeks!!!)
Also, if you raised your Boston Terrier from puppyhood, that should bode well for your qualifications to adopt Amber. Not that the breeds are exactly the same, just that you know what you're getting into with a very young pupply.
Good luck, and if it doesn't work out--I recommend checking into rescues in your area or looking at Petfinder regularly.