Hello. Thanks for asking from HCM. I can understand your concern. According to history, you are still having swelling and bruise at injury site even after 1 month. Usually, both swelling and bruise disappear in 14-21 days. If both persist, other causes need to be considered like infected hematoma, calcified hematoma, chronic hematoma in scalp muscles. Hematoma is defined as collection of blood at injury site. Skin and subcutaneous tissue has a tendency to absorb blood. When infection occurs in bleed, reaction prevents absorption. You can feel soft swelling with pain and redness. Fever can also occur. In case of calcification, swelling becomes hard. Usually skin colour remains normal. Chronic hematoma in muscle occurs in temple muscle mostly. Swelling remains soft. Pain occurs after muscle movement like chewing or moving jaw. You can correlate your swelling with above mentioned features. My advise to you is you should not ignore it. Consult doctor and you may be advised Xray skull or CT scan of head to find out about swelling and its extent. Swelling might need surgical evacuation or aspiration if collection is there. Thanks. hope it will help you. Take care.