Hi I Had A Home Pregnancy Test On Aug. 20

Hi I had a home pregnancy test on Aug. 20 which is was positive. I started to spotting about 6 days ago. I went yesterday to the clinic they did an US vaginal and they said that there's no embryo. They believe is an incomplete miscarriage or an ectopic pregnancy I don't have any symptoms of ectopic. They want me to go to the ER I haven't gone. they said to go tomorrow to the clinic for another HCG blood test. Would the blood test detect that I have an ectopic pregnancy??