Can breathing in gasoline fumes get you sick?

Yes: Volatile fumes from gasoline, glue, paint, etc..., are bad because they diffuse throughout the body after inhalation. The fumes one smells at a gas station are diluted by the air, so don't cause illness. If one purposely sniffs gasoline or glue, or accidentally gets too much fumes while painting inside a closet, he can get damage to the lungs, brain, etc..., especially with repeated exposures.

Sometimes: With most chemical fumes/smoke the amount of harm depends on the length of exposure, how much and whether or not you were in a well ventilated space (or wearing protective equipment. Ask your question again with a bit more details about your exposure.