I'm 34 days late, negative tests

Elizabeth • As normal as I can be without being very normal
I'm freaking my fiancé out. I'm 34 days late and I have no idea what's wrong with me. I took probably 3-4 tests so far and all are negative. I gained at least 15 pounds over the last few weeks and I look horribly bloated. 
Should I go to the doctor?