My 4-year-old female Teddy is free-roaming; lately her breasts enlarged, nipples turned pink, and abdomen grew larger. Is she pregnant?

Based on your description, the symptoms look like pregnancy. Early pregnancy shows breast swelling and vulvar discharge, and behavior changes such as clinginess, bigger appetite, sleepiness, and less activity. But a false pregnancy in females shows similar signs almost identical to real pregnancy, so it is hard to tell apart.

False pregnancy usually comes from long-term heat causing hormone imbalance or improper mating, and typically returns to normal on its own after a while. To confirm, take the dog for an abdominal ultrasound; if pregnant, sacs appear and the due date can be estimated.