After looking at the pics, I have to agree with the others, it appears to be an ingrown hair. Using a hot wash cloth will help it rupture on its own. It does NOT appear to be an ulceration of any kind as the area around the spot is still fairly normal looking. An ulceration would be MUCH much redder.
I can understand the painful part, I’m sure it does hurt. I do disagree with the majority here in regards to “popping” this thing. If it is an ingrown (which it does look like) the sooner its open and the hair is pulled out, the faster it will heal. I do recommend that you use hot compresses and allow it to rupture on its own, however, if you aren’t the patient type of person (like my spouse) and it is very very white on top, go ahead and rupture it.
It will feel better once it is open and the icky stuff is allowed to drain out. If you are super concerned about it, go see your doctor.