Hello,
How would I know if my dog is pregnant. This accident happened last Saturday ( a week ago).:confused:

Take her to the vet.

Take her to the vet. And if she is not pregnant or in heat, PLEASE get her fixed. I don't know how many times this has been said, but PLEASE fix your animals. The shelters and humane societies are full and wonderful animals are dying daily simply due to ignorance on the part of the animal-owner. Sorry for being harsh, but this is ridiculous.

If she was bred this recently, your vet may be able to spay her as soon as she goes out of heat, before she shows any signs of pregnancy.