It sure as hell can be herpes but on the other hand, it may not be since the puss doesn't make sense but if this thing is still there, you need to go right this very second to a Doctor and get it checked out before it goes away!!!! Don't wait to see a Dr. GO NOW!!! Once it disappears, it will be a guess on what it was and can take several months before showing up in a blood test!! GO NOW!!!
I answered this over in the STD forum. :)
Aj