It is never a good idea to pop a pimple. Pimples are sacks of bacteria that, when popped, contaminate the surface of the skin, which can lead to more pimples. Squeezing pimples may force bacteria deeper into the skin, which can cause an infection, according to WebMD.
Popping or simply picking at a pimple may also cause it to become red, inflamed, swollen and infected. It is also common for popped pimples to bleed and scab over. On their own, pimples heal within a week. If they are squeezed or popped, they can linger for several weeks and may even scar permanently.