Pimples occur on the skin when pores become plugged by dead skin, makeup and other debris, allowing bacteria and other substances to build up behind the blockage. It is possible that the makeup that you used was the cause of the pimple outbreak. However, an allergic reaction to a makeup ingredient would be different, resulting more in red, inflamed skin, not pimples necessarily. If the makeup was the cause, it would be simply because it made the clogging of your pores worse.
In the case of pimples, these may take some time to resolve, even after you stop using the makeup. This is because the blockage of the pores has already occurred, and inflammation has set in. You can help the process along by gently washing your face with a good facial soap, followed by exfoliation or the use of an acne
preparation such as benzoyl peroxide or salicylic acid to help clean out the pores. You should definitely avoid squeezing the pimples or picking at them, as this can lead to worsening inflammation and possibility infection of the skin.
If your symptoms do not begin to resolve in the next few days, you may want to see your primary care doctor
for more advice.