Hi This could be a hematoma following the bruise. This shouldn t be a problem however you can take warm compresses and it s bound to disappear in a few weeks. This lump could have been there the trauma and maybe you just noticed it now. There are a couple of benign swellings anyone could get such as a dermoid cyst or sebaceous cyst or a neurofibroma. Final diagnosis requires clinical examination and if this apparent hematoma doesn t subside in three weeks you can visit a local general surgeon for this. Assuming that it s a hematoma I d advise you following treatment for a period of five to seven days Warm compresses thrice a day Ointment Thrombophobe twice a day to be applied over the swelling Tab. Voveran 50mg twice a day Tab. Serratid 10mg twice daily. Hope this helps Regards