Your description is highly suggestive of muscle injury
- a few fibres might have given way?
When there is pain, rest the part / give cold compress / take Over-The-Counter pain reliever with or without muscle relaxant
- for a day or two.
If there is any doubt, you must see a doctor.
If there is no improvement / if there is fever
, bladder or bowel symptoms - you must go to the doctor immediately
Wish you speedy recovery