Ejaculation is when semen and sperm are released from the penis. It usually occurs when a man reaches orgasm. You may fail to erect again after ejaculation because you are tired, stressed or anxious. After ejaculating, people can vary in the amount of time they need to erect again, from minutes to hours or days. There is NO time limit-the body will return to the erect state once it has rested and is stimulated again.

Attribution: Straight Talk Foundation