"Pops?" That sounds like bad news.
Here's what I looked up from NIAMS.gov
What Are the Signs of a Torn Rotator Cuff?
Typically, a person with a rotator cuff injury feels pain over the deltoid muscle at the top and outer side of the shoulder, especially when the arm is raised or extended out from the side of the body. Motions like those involved in getting dressed can be painful. The shoulder may feel weak, especially when trying to lift the arm into a horizontal position. A person may also feel or hear a click or pop when the shoulder is moved.