What are some signs of abscesses due to abdominal injections for diabetes. Medication used is insulin?

Redness, Pain, warm. Skin infections can occur with any break in the skin. Staph bacteria live on your skin. Sometimes that bacteria can cause an infection, especially when the patient is more vulnerable to infections like patients with diabetes. Do not delay to see a doctor. Antibiotics are needed. Sometimes incision and drainage. Sometimes hospitalization.
Redness/pain/fever. Skin abscesses due to Insulin injections should be rare. If one takes the proper precautions and uses clean, one time needles, alcohol preps to the skin and uses good technique, this should be rare. If develops, there can be sterile abscesses without redness or pain or fever but if non-sterile, then heat, redness, pain, streaking, fever, chills etc can happen. See your doctor and get checked.