I Have What Appears To Be An Infection At The

i have what appears to be an infection at the site of a flu shot injection. It is hard, raised and very red and sore when pressure is applied. i was advised to see my physician. he first prescribed warm compresses which was tried for six days to no effect. He has now lanced it and I am taking cefuroxime axetil. The site is still red raised and hard after three and one half days. As far as I know, no culture was done, but it may have been done without my knowledge. Is this antibiotic appropriate for a subcutaneous skin infection? What should be tried next if this antibiotic doesn't cure it/