Hope this message finds you in good health.
I have gone through your complaints and understand your concern.
You seem to have injured your breast soft tissues causing hematoma
which generally take around 3-4 weeks time to heel.
But still,it will eventually heal.
Take analgesics,anti-inflammatory tablets,ice packs,rest.
Possibilty of breast cancer
is very rare
Nothing to worry about.
I hope your question has been answered.
If you have any follow-up queries,feel free to consult me anytime.
Thanks,Take care,God bless.