Thank you for posting your query.
There are two likely possibilities for your symptoms:
1. Infection- it can lead to bruising, pain and swelling over the back. In addition, there may be fever
and increased warmth over the affected area.
2. Small hematoma- blood collection in the soft tissue
. This is more likely, if there is any injury
of the affected area, or if you are taking any blood thinner medications.
An examination by a doctor can clarify the issue and help in planning treatment.
Wishing you good health,
Dr Sudhir Kumar MD DM (Neurology)
Senior Consultant Neurologist