My baby daughter's arm got hurt somehow, she cries when i try to lift or move her arm. what could this be and how do i treat this?

Have it evaluated: It is hard without a review of history & exam to guess the problem & suggest a treatment. Toddlers can dislocate their elbow falling backwards with arm outstretched or if picked up by the hand. They can also have a variety of problems causing similar cries. The sooner it is evaluated the better the healing if dislocated.