Could my dog be sick or pregnant?

Question: 

My 8 month old dog just finished her first heat and now has slightly swollen nipples. She has not been around any other dogs. Should I worry?

Answer: 

Swelling of the mammary glands is normal during or just following a heat cycle. You may also notice swelling of her vulva. The behavior (humping objects) is also normal, and will often subside once she is spayed.