What Causes Recurring Blister On Nose?

I have a reoccurring weird pimple on my nose. It has no head on it, but deep under the skin. I can see white under the skin. I popped it was thick and stood up like a wooden match. No fluid in it. Smell a little like sweat. Left a whole in my skin. Comes back in 3 to 4 weeks. Never had anything like this before.