Ok just wanted to make sure you knew whether your specific pump was safe for re-use or not (not all are). This is from an article from babycenter.com:
"Note: Though it may be tempting to share or borrow a friend's personal-use breast pump, or buy one used, the FDA and breastfeeding experts caution against it. Breast milk can carry bacteria and viruses — including hepatitis, HIV, and cytomegalovirus — that can contaminate these pumps and pass an infection to you and your baby. Because droplets of milk can get into the internal parts of these pumps, using your own collection kit doesn't necessarily make them safe to use.
Pumps designed for multiple users, like rental pumps and hospital pumps, don't have this problem. They're designed to prevent breast milk from getting inside the pump. So as long as you use them with your own personal collection kit, they're safe.
To find out whether a pump is okay to use secondhand, check the packaging or call the manufacturer. If it's designated as a "single-user" pump, it should be used by only one person."