Doctor won't give me a blood test

So I'm over two weeks late and have no signs of a period. I took a pregnancy test on the 31st of March and it was bfn and again this morning and this test was vvvvvvvvf. I called my doctor and she said they could give me a pregnancy test but only that she basically refused to give me a blood test. She told me that if and only if I was pregnant with the pregnancy test than she could make another appointment for a blood test. I'm so pissed.! I just want to know if I'm pregnant or not and if not I want to figure out why I'm not getting pregnant. I've been trying with my fiancé for over a year and nothing. It's so frustrating. Any advice??? Or anyone have similar stories?