My daughter has some type of blister on the tip

Patient: My daughter has some type of blister on the tip of her finger that is moving down into her fingernail. Its swollen and green and yellow in color. What is this?

Doctor: Hello thanks for your health query on ATD.It appears that your daughter has developed bacterial infection of fingert ip, leading to accumulation of pus. Please see a surgeon ASAP. She may require antibiotics as well as surgical drainage.Hope you got me