Me And My Husband Started Trying To Have A Baby

Me and my husband started trying to have a baby in September, I got my period on September 12th and I regularly have a 28day cycle. It is October 24th and I still have not got my period, putting me at two weeks late. I took a home pregnancy test last week (one week late) and it showed negative. So I thought maybe i was just late, however now i am two weeks late and still haven't gotten my period. this past week I have been nauseated on and off and not feeling like myself. Should I go into the doctor for another test and ask for blood work to be done?