vaginal discomfort,no period and plenty of neg--- test

Hi I am a 34 year woman who has been trying to get pregnant for a while now. I've had 2 miscarriages in the past. And lately I've been getting discomfort in my vaginal and lower abdomen and heartburn and nausea. I don't know what to think anymore, ive tried several different home pregnancy test and they all say neg---- and i went as far as paying a clinic to take a blood preg test and then they said it was neg---...So what should I do ????? I really want to be pregnant!!!!!