Bleeding

Question
I have a Dog who is 5 years old. We have not gotten her spayed yet because we are still undecided about whether or not we want her to have puppies. I read online that "periods" in dogs average about a week.  She has been menstruating for 3 weeks now and we were getting worried because she normally does not bleed for this long and not nearly this heavy. She seems very sad lately and shes not sleeping good.  Should we take her to the vet or let the situation pass and hopefully she'll be fine.

Answer
Ok it's not a period. Periods in women are when their bodies are sloughing material that was stored to sustain a pregnancy that doesn't exist. For a dog it is a hormonal change that allows them to become pregnant. Therefore it is called estrus. She will be in heat for three weeks. Usually breeding can occur beginning around the 13th day. If she is behaving abnormally , then yes you should take her to the vet The hormonal fluctuations can cause moodiness.
Make sure she's ok physically first.
thanks,
Cindi