I had a lumpectomy. Can I ask what the symptoms of seroma are?

Fullness, drainage. Seromas are fairly common after lumpectomy, should be distinguished from a hematoma (blood clot). Both can present with fullness (and discomfort) in the area of the surgery and drainage, although hematomas tend to drain bloody fluid and present earlier than serums. Treatment generally includes repeated aspirations in the office until the seroma resolves. If it is red, abscess if possible also.