Brief Answer:
follow the advice, observe how you stay afterwards...

Detailed Answer:
Hello there,
Welcome to 'Ask A Doctor' service...
I've gone through your query...

Well, first of all, if there's any recent onset activity which could've caused such stress/trauma to the shoulder and it's surrounding muscles (rotator cuff is just one among them), then better to avoid it altogether as a beginning...

If it's a recent issue then applying ice-pack over the area three to four times daily for the next 1-2 days would be helpful...

For pain, taking round the clock pain-killer such as Acetaminophen/Tylenol (650mg three times daily after food) or Ibuprofen 400mg twice daily after food for the next 3-4 days would be beneficial...

Along with it, and most importantly, you need to give the affected shoulder rest...Don't involve into any strenuous activities for the time being...Strictly avoid any overhead hand rising...

Additionally, a shoulder strap/immobilizer can be put on to help keep the shoulder rested and immobilized for the time being...

All these will help to self-management of the rotator cuff issues...

However, if despite following these, there's a persistent increase in pain/any progressive swelling-redness/weakness over the shoulder/upper arm then better not to wait any longer and get it examined by any Orthopedician along with getting an X-ray of the shoulder joint done to look into the extent of the injury...

Let me know if I can assist you further...
Wish you good health...

Take Care
Kind Regards

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