I got my first Prolia injection 3 days ago, now just waiting every day to see what happens. A common side effect is back pain, I already have chronic back pain so I don’t know how I’ll know if Prolia causes any. My new endocrinologist wants me on it for 2 years, then Reclast or Fosamax. I may try to convince him to switch earlier than 2 years, but that’s a future problem at this point. Wishing you best of luck with your treatment!