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Pain is due to soft tissue injury
Lump is due to collection of blood in the soft tissue ( haemetoma ).
Apply ice 3 to 5 times a day.
gel locally on neck and shoulder.
Start nsaid with serratiopeptidase
Intra muscular injection of nsaid advisable if pain is severe.
If pain is persistent then go for x-ray and start medications under guidance of orthopedician.