Ouch - that sucks
If it is infected, you should definitely have it seen to.
You might be embarassed to show a doctor your penis, but trust me - they see intimate parts of people's anatomy regularly as a part of their job.
I think a bit of embarassmemt would be a lot less troubling than a serious infection and any possible complications that could arise from it (no pun intended).
I'm not a doctor, but pus in an injury in that part of your body is not a good sign. Get it checked out mate - i know a lot of doctors and nurses, and people's genitals needing medical attention is extremely common (from STI examinations, inserting catheters - all manner of stuff).
It's an important organ, to state the bleedin' obvious - i think you should go see a doctor.
I know how painful it is (done similar myself - and i've been really careful ever since. Hurts a lot and can take a while to heal.
The the best - i would suggest that you be really gentle when it does heal up; it's too easy to have it snap again if you have sex too soon and it's still fragile.