Suggest Tests To Confirm Pregnancy

3 years ago i had a c section and tubes clip and burn now im eating alot feet swollen headace nipples hard,ive taken pregancy test all negative,the same when i was pregant with my son.my husband says im pregant i say no.i need to know how can i be sure before i go see my obgyn.im 44 years of age ive had all signs except throwing up with my son.oh i do have heart burn ,go to the bath room alot .please help me