How long does it take for a dog to show signs of pregnancy?

Hi my name's ashley and I'm 13 years old and my cocker spaniel dogs got stuck together about 20 days ago and my female cocker spaniel hasn't been sick or any thing. could this mean it's a false pregnancy or is it good? she's been acting the same as usual...

and still jumps on the furniture without any problems...I can tell that around her ribcage and back area that it's getting a little bigger, and so are her nipples. but that may just be me exaggerating. my little sister tries to pick her up by holding her by her butt and chest is it okay for her to be held like that? and also I read that you should give a pregnant dog about 1/2 a hard-boiled egg every other day we've tried this method and her appetite has seemed to increase...I want her to have puppies but I'm not so sure how to tell exactly because as I said, she been gradually getting bigger but not by much.

Ashley, if your dogs got stuck she is probaby pregnant. There is a lot that will be going on, you should ask your parents to take her in for a vet visit to make sure she is healthy and that she is pregnant.
An egg is good,I give my girls 1 every other day in the last month they are pregnant.
She will need to be on a very good dog food that has a lot of protein in it and she will want to eat a lot more than she usually does. As far as taking care of her, she shouldn't jump over things and you should make sure she goes for regular short walks. In the coming weeks PLEASE send me fun mail with any quetions. I will be glad to help as much as I can.

From what you have informed, I think she is pregnant. Just make sure your sister doesn't carry her in harmful way that can harm her puppies insider of her. And about the egg thing, I have never heard of that and I'm not to sure that it will work. Just make sure you just feed her dogfood and that should do the work. Table food can harm your dog later in the future. It's not healthy, therefore just feed her the dogfood and plenty of water.
Hope my advice helps
=)
Oh dogs give birth around the 90th day.

The egg is fine for her. Egg is something your pregnant dog can eat.

Dogs give birth about 63 days after they have first been bred, Did you mark on the calender when they hooked up? You need to know this and then count the days and mark on the calender when she is due.

You dog my really show until the last two to three weeks. We have a lady on Funadvice that breds Cockers. I will ask her to add what she can.

does the female have to be in heat in order to be pregnant?

yes they need to be in heat in order to get pregnant when you notice the first sign of blleding count ten days later and that is usally when she is ready to be with her mate her tail is one sign to look for it will go staight to the left or rite when she is ready for a male to mount her...