Small whitehead directly on lip. comes when forgetting to put on chapstick at night. goes away after popping. not a blister. exactly like a whitehead?

Rule out skin cancer: By the "lip," it appears you mean the vermillion, red part of cupid's bow.This skin is unlikely to get a "whitehead." It is skin which is sensitive to sun exposure, chemicals, trauma, cigarettes. The lip can easily get precancerous and atypical cells. That can lead to skin cancer - basal cell or squamous cell. I would recommend seeing your doctor, possibly a biopsy. "Popping" may be harmful.