I had a pimple on the shaft of my penis and it popped and a pimple seed can out of it.i whiped it with alcohol should i be worried and what shall i do?

See a doctor: Pimples on the shaft of a penis can be a sign of sexually transmitted disease. The skin of the penis is not a common place to get acne as it lacks the sebacious glands from which acne forms. Don't have unprotected intercourse in general but DEFINITELY not until you see a doctor. Many county/city public health clinics offer free confidential exams. Start by googling "STD clinic"