Preejaculate refers to the oozing of fluids that precedes ejaculation in many men.
Yes there are small amounts of sperm in it, and yes you can get a woman pregnant with it.
Maybe because the sexual excitement receded. Pre-ejaculate is produced by the Bulbourethral gland in preparation for the ejaculation of semen (ejaculate).
No. Pre means before and the pre-cum is to clean the urethra before the ejaculation.