suspected ectopic but no urgency?!

Hello hope someone can help or share their experience.

I should be almost 9 weeks now. However at 4 weeks I had a heavy one day bleed. I have been spotting brown ever since. I believed I had miscarried, but was still getting positive tests weeks later.

Finally I was accepted at the early pregnancy unit, where an ultrasound (internal) showed an empty womb and seemingly clear tubes. I was very embarrassed as the nurse pretty much said i was lying about a positive test the night before. She had me do a urine test there, and was visibly surprised that it came back positive. 

Anyway, just over a week later, I am still none the wiser. I have had another ultrasound showing nothing, four blood tests showing very slow and low increasing hcg (115, 137, 145, 177), and i have seen their consultant. 

I am repeatedly told it could be this or that, but they still have me as high ectopic risk. The nurse is now putting me in contact with the TOP consultant to formulate some sort of plan of action - she is seemingly unhappy with the first consultant saying just wait and see and watch bloods. Wait for what? Rupture? The bloods to continue popping up for the rest of my days?! 

I am so frustrated, exhausted and drained. I am having all my pregnancy symptoms and emotions but no baby. I just want this over but dont know what to expect anymore as they all seem very baffled just like me.

i had the mirena coil removed a month before falling pregnant but dont know if that is a link or if im clutching straws for answers.