A blackhead is a bump or plug on the skin, usually yellow or black in color. It is a type of acne caused by excessive oils from glands, not from poor hygiene. The black hue is caused by light reflecting into the pore and not from a black substance inside. While they are gross to read about, they are even grosser sitting on your nose, mocking you.
Instead of obsessively staring into a mirror and squeezing those bumps, apply lemon juice to them using a cotton ball or a cotton swab. Leave the juice on overnight. In the morning, rinse your face with cool water. Repeat every night for 1 week.