Yes, if you have seen your dogs mating twice, then your dogs are both sexually mature and can indeed have puppies.
Since you're not mating the two dogs to produce pure-breed pups, it's alright if they male mates at this age, anything after 10 months of age is acceptable. The younger the dog, the more distressed it will get when it gets pregnant, and the more you'll have to take care of her.
If you do not want to mate the dogs, I would suggest getting the female spayed and the male neutered to avoid potential accidents as the female will go into heat twice a year and at either of these times only one mating can produce puppies.
Since you're not mating the two dogs to produce pure-breed pups, it's alright if they male mates at this age, anything after 10 months of age is acceptable. The younger the dog, the more distressed it will get when it gets pregnant, and the more you'll have to take care of her.
If you do not want to mate the dogs, I would suggest getting the female spayed and the male neutered to avoid potential accidents as the female will go into heat twice a year and at either of these times only one mating can produce puppies.
