Positive hpt negative blood test?

I dont know what to think today. I got a few pretty faint positive test and went in today for a blood test since i just came off the depo ahot in January. Im 11days from what i believe is when my period is due but because we dont know what my periods are going to be they went ahead and did the test. Before i got the test done the nurse told me i probably had a miscarriage and that they would check my levels to understand more of whats going on..now im confused because i have very pregnancy symptom i have had in the past and i haven't bled very heavy at all. I have had two miscarriages in the past and they always was heavy and i cramped really bad with them..which i havent done this time. I did this with my daughter last year..i had a blood test done to early and two weeks later i had a positive test done with blood work..so im nervous now because i know the nurae is going to tell me its a very early miscarriage...i dont know what to think..has anyone had the same thing happen to them?...a few happy endings would be great...