My cat is a year old, last WK, she delivered a kitten, that was very premature, and not alive. She spotted blood a little after, not long. I assumed that was going to be it. ....well now, she's lost a mucus plug, she's bleeding, and acting to be in active labor?! Is this Normal, or an Emergency situation??
You should take your cat as soon as possible to your veterinarian.
She could suffer a uterine infection due to abortion, which carries a great risk to your cat's health and life. The reasons for abortion can be very diverse. Usually, abortion happens due to infectious cause and viruses. You should take your cat to your veterinarian as soon as possible so he/she can examine her and take the necessary steps to remove the remaining foetuses that have not been expelled yet.
All the best,