Neg blood test and negative hpt's, how can I prove I'm pregnant when my dr has dismissed me?

Why do you think you are pregnant?

Blood tests are very accurate at detecting the pregnancy hormone, this hormone must be present to get a positive result.

How far along do you think you might be? If you happened to test too early, you would simply wait a bit longer and test again. At some point you would get a positive if you were indeed pregnant.