thanks for writing us..
Better if you would have mentioned your age , sex and any co existing illness like Diabetes
As i get your information your shoulder and arm pain
is musculoskeletal for that better you consult one orthopedician and get X ray
of concerned part..
If you feel your heart beat irregular get one Holter monitoring done that will check your 24 hrs ECG
Dont be panicky . nothing looks like serious, i will be happy to answer you after repors..