That link doesn't work for me. At the very least, I'd use antibiotic ointment on it. It sounds like it was, in fact, a pimple or ingrown hair, and in your attempt to pop it, you aggravated the problem. If it is an infection and continues to be painful, you should see your doctor RIGHT AWAY. A spreading infection requires at least oral antibiotics, and the correct antibiotic would be determined by the type of infection. Don't let it get out of control, or it will require surgery. If it starts to go down, or at least doesn't get worse, with topical antibiotic cream, then just let it heal and don't keep touching it.