I hope you will take the time to read this.  I suffered from PPD--just didn't know what it was--for several months after having my daughter.  A friend who was a nurse finally gave me a book called "This Isn't What I Expected" and it was enormously helpful.  This link, while not related to that book, will provide valuable information on PPD, signs and symptoms, PPD vs. "the baby blues" and what to do if it continues.  Best wishes to you!

http://www.womenshealth.gov/FAQ/depression-pregnancy.cfm