4 kittens, 24 hours later and still harboring more

I have a new mama and she gave birth to 4 kittens, first one i think she smothered with her arm while cleaning it. She gave birth to three more, the third one she didn't even know she had, I cleaned it and put her head down there to do the umbilical cord stuff.. she did that and took over the rest. Although i don't recall the placenta comming out though.

She quit giving birth after that but we feel that she still harboring one or two because her tummy is still big. Is it possible that the placenta blocked the birth cannal for the other's to be born?

It's been 24 hours now. Has anyone ever heard of kittens being delevered days later? Could they have been from another cat a week later and they are just waiting to develope? Is there a chance they may still be alive?

I'll be calling the vet in the morning to find out what to do? I can't help but worry.

Coco had 3 Kittens all by 6 Am the about 15 hours later my Sister calls me and said it looked like Coco had contractions again. When she is on the phone with me a dead Kitten comes out. She goes to bury it and another dead one comes out. The Vet had told me she was having 3 Kittens but there was 5. Her labor stopped too and she acted normal. The 2 dead Kirother Cat had 2 Kittens were Male Calicos. My Brothers Cat had 2 kittens 2 days after she had my Sasha. They died though. I would go to the Vet and not wait if you think there is more. shadow almost died because there was a dead Kitten inside her and it was mumified. Cats can be fat after having Kittens Coco was huge because she was full of Milk.