Go to the Doc as soon as possible. Don't put it off as its not going to get better on its own quickly. Antibiotics and possibly eventually a minor incision drain. Hot compresses will centralize the infection. Then it will likely either be cut to drain or eventually form an abscess. So go get some antibiotics and the start the compresses until you can get this drained. Don't wait.
For future use please look at your injection procedure. New nail every time.. why to avoid this shit, its so easy cheap, saves your veins and eliminates chance of communicable transfer. . Disinfect injection site because most of the risk of bacterial infection comes from our own skin.
