I am sorry that your mother is in pain. It probably seems like a muscle sprain but cardiac problem needs to be ruled out which can be fatal at times.
Please get an ECG done for her. If it is normal, then we can look into other causes. The shoulder pain
may be due to a sprain at the cervical spine
level, it could be a shoulder joint pathology, it can also be due to cervical spondylosis
. For all of these, NSAIDs like Ibuprofen
may be taken.
The change in her voice will get back to normal soon; do not worry about that.
I hope this helps you. Please take your mother to her primary care
physician and get the basic investigations done.
I wish her quick recovery.