My pug had puppies and I left the door open and my doxie killed all the pups. I haven't been able to pet my doxie since this happend. Is she a killer?

My pug had 3 puppies, and 5 days later I accidentally left the door open to where the puppies were, the mama pug came outside with me and while we were out, my adult female doxie killed the puppies. I am worried that there is something wrong with my doxie. I haven't even been able to pet her since this happened. These adult dogs have lived together for 4 years. Last year they had puppies together and after the puppies the doxie got spayed. Is my doxie a killer?

Thanks for your help.

Laura Black