Does A Female Dog's Tits Swell When She First Becomes Pregnant, Or Does It Not Necessarily Mean She's Pregnant?

The nipples will swell some when the dog come out of heat reguardless. So it does not mean that she is pregnant. My little chihuahua's nipples did that some after her first heat and I was begginning to wonder if my male chihuahua had accidentally bred her because at the time he was not old enough. They just swell some.