Has this happened to anyone else?!

I have had very regular periods since stopping birth control trip in March of this year when we decided to try to have a baby. I had my last period October 21st like normal. November came, no AF. December came, no AF. I have been to the doctor for blood test I. The beginning of this month which was negative. I went for an appointment last week and they told me that my urine was negative but she would not run anymore tests. She basically told me that she believes I have stopped ovulating due to my weight and I should lose weight and try again. I’m not convinced that she is correct as I have been having normal periods until two months ago. Has this happened to anyone and you were still pregnant?