What Causes Swelling In Right Parietal Bone After Accident?

hello sir, my mom met with an accident yesterday,there is a swelling in right parietal bone,it is hard and tender, at the time of accident she gained conscious quickly, no nasal or ear bleeding no vomiting sensation still now she is oriented. she was given first aid in a nearby hospital and told nothing to worry. what is mothers state is there any need to take scan.and what is the cause for the swelling will it be a problem later on