Go to a walk in clinic or the ER, they'll give you a blood test. By 3 weeks the HCG should be in your urine stream. I doubt your pregnant, but you never know. Frankly, either way I would switch doctors. It would have been easy and given you an answer right away and put your mind at ease. She should have done it!
pregnancy is possible,but a blood test would be accurate,generally a HPT would be accurate if already 3 months have passed.its not for her to say blood test be waste of money,it aint her money.an ultrasound will confirm,but there could be many reasons.good luck,