Staph infection

Patient: I had what I believe was a sebaceous cyst on my back last week (it had been a white lump under my skin for about 2 years). One day it was very red, sore and swollen with a head on it. I had the puss squeezed out of it 2 nights in a row, but by the 3rd night it was too sore to squeeze or even touch. I went to urgent care and they said it was a staph infection and put me on antibiotics and pain meds. It is now 4 days later and the area is still very swollen, red and purple in color and terribly painful. Do I need to go back to the doctor, or has it simply not been long enough for the antibiotics to take care of it yet