Why can't I lift my arms after my mastopexy, augmentation, and lipo? (Photo)

I don't see anything alarming in the photograph. You may be fairly sensitive to pain it would be useful to know whether or not your implants are under the pectoralis muscle. Specific complaint should be discussed with your plastic surgeon.

From the photos it appears that you have a nice outcome, with normal healing. When you raise your arms, the pectoral muscles are working around the new implants and that can cause some discomfort. Byt 3 weeks, it is a problem if you can't use your shoulders.A visit to your surgeon is advised. He or she may well suggest a course of physical therapy to restore your motion before you start to develop a "frozen shoulder."All the best.