I would like to purchase a nice carrier for Dixie, but I am concerned that if I buy one too soon she will outgrow it. I did buy one [not tooo expensive] so she will become comfortable with the concept. It really hurts my shoulder though. Thin strap cuts into shoulder even though she is only 3 lbs. I would hate to put down more $$$ on a designer tote and find it too small in the near future. Any ideas when a fur baby is full size?