Hello and thanks for the query
The symptoms you have explained in your query are surely be an infection but it can be sue to the bite that later on get infected. You immediately needs a proper effective antibiotic course to get control over the infection. In addition to this:
1. Get the aseptic dressing of the site daily till the pus stops.
2. Do not touch the the bump with non-sterile hands or instruments. Can apply aseptic creams and lotion.
3. Take analgesic
and anti-inflammatory drugs for pain.
4. If it is itching than you can take antihistamines like Cetirizine
Consult your physician immediately and get the proper treatment.