My back was hurting tremendously and my husband was trying to help stretch and he pulled my arms too far back. 1.5 weeks post-op

Dear hdiane,  I understand your concern. However, without a proper assessment it would be difficult to determine what is wrong. It is best that you visit your plastic surgeon for further assessment. Only after thorough examination you can get proper recommendations and advice.Daniel Barrett, MD
Certified, American Board of Plastic Surgery
Member, American Society of Plastic Surgery
Member, American Society of Aesthetic Plastic Surgery

Probably not. When concerned, though, always best to be evaluated in person by your surgeon. At one week you are about 5 percent healed, shaped, softened, dropped and fluffed. "Drop and fluff" refers to the fact that as the skin stretches and the muscles relax, the implants move down and out slowly – about 1 percent a day. It’ll be about six weeks before they even begin to settle down, but they’ll be close to 80 percent settled and softened at three months. Watching their progress is like watching your hair grow. You don’t see a difference in your hair growth daily, but all of a sudden you need a haircut. 
Be patient after surgery. Give yourself a few months before making a judgment about your surgical results. You won't know the outcome until then. 
Dr. Ted Eisenberg, Board Certified Plastic Surgeon and Author

I assume your implants are submuscular thus your concern.  If you didn't have swelling or bruising then I don't think you tore or disrupted anything.  Best of Luck.

While it is unlikely that you have done any real damage, it would be a good idea to let your surgeon know and have them take a look.

This is a question you have to ask your surgeon.  You will also need a physical examination.  We usually do not put sutures in the area that you felt pain.  However, that area is stretched upon placement of the implant and some tissue fibers are intentionally stretched during surgery.  I would advice that you go see your Plastic Surgeon.