There are different types of ejaculation disorders, including:
Premature ejaculation -- This refers to ejaculation that occurs before or soon after penetration, usually 30-60 seconds after penetration. Three minutes or longer is considered normal.
Inhibited or retarded ejaculation -- This is when ejaculation is slow to occur.
Retrograde ejaculation -- This occurs when, at orgasm, the ejaculate is forced back into the bladder rather than through the urethra and out the end of the penis.