You might be having a case of post traumatic myositis
ossificans(bone formation in the muscle at the site of the bruise
).An X ray will help with the diagnosis . It could take months to resolve on its own. Physiotherapy
is helpful to improve the condition.
Another possibility is that the trauma directed your attention towards the bone (benign bone tumor
etc).Do visit your orthopedician to rule out other conditions.
Have a nice day :)