Stillborn baby 6months ago

Hi everyone. Im 20 years old and i had a stillborn baby may 1st 2014. And wince aug 1 2014 my bf and i are trying to have a baby but nothing is working we have intercourse but nothing. My periods have been pretty werid one month it was regualr another month its 30 days late and then i just had my period in nov. It was heavey but only last 3 days . I took to test negative. Would someone please give some advice please i really wanna have a baby yes i know im young but my life was only about my baby girl at the time i got pregnant after i gradute high school.