What you have sounds much like Folliculitis.
Folliculitis. is inflammation of one or more hair follicles. It can occur anywhere on the skin. Folliculitis starts when hair follicles are damaged by rubbing from clothing, blockage of the follicle, or in your case, shaving. Most of the time, the damaged follicles become infected with Staphylococcus (staph) bacteria. Which would cause the large amount of puss you mentioned. I would not recommend popping it as your your at risk of infection increases since bacteria can easily get in. Instead you may help your body push it out with a worm compress. Once it does pop you should let it drain by covering the area with a clean gauze changed frequently, avoid getting the area wet as it needs to drain and dry out. Do not use excessive amounts of hydrogen peroxide to try to clean out the affected area. Hot, moist compresses may help drain the affected follicles.
Treatment other than simple first aid can include antibiotics applied to the skin (mupirocin) or taken by mouth (dicloxacillin). If its suspected a fungus may be the cause, but unlikely for your case. an anti-fungal medications may be used. Folliculitis usually responds well to treatment, but may come back. Folliculitis may return or spread to other body areas.
When the area heals you will notice that the color is a purple hue but that is normal and should diminish with time. When shaving try to use a new razor and don't pull on your skin to expose the hairs as when you release the skin the freshly cut hair will retreat beneath the skin pulling possible bacteria with it, thus causing a problem. If shaving continues to cause you problems, consider alternatives such as waxing or chemical hair removal or even laser removal. if things do not improve please see a professional health care provider. thanks
you should be seen within a week or so to have this looked at. it doesn't sound like herpes but more so like ingrown hairs or even a bacterial skin infection. no more shaving down yonder until you know what is going on and either toss the razor you used or properly clean it if it's not disposable in case this is a bacterial skin infect you are spreading around .
grace