Can HCG Levels Be Detected Post Miscarriage?

I recently confirmed through a home pregnancy test that I was 1-2 weeks pregnant, which scared me due to the line of work that I am involved in and never told my employer or immediate family. I took another home pregnancy test 2 weeks later (Feb 10/15 and tested positive stating I was 3+ weeks. Shortly after confirmation of first pregnancy test, about 5-6 major stressors (work and personal problems) on Feb 13/2015 I stared to miscarry. But I never got a chance to go into my doctors to neither confirm not deny the pregnancy...it is now the Feb 19/2015. (6 days later after miscarry began) is it possible for my hCG levels to still be detectable for confirmation of pregnancy/miscarrige?? Due to the work and personal stressors on top of losing my unconfirmed pregnancy via doctor through blood analysis or urinalysis tests, only confirmation I had was via home pregnancy tests. I am looking to go on a "stress leave" of absence from work to handle all the issues I am currently dealing with, not to mention I haven't had a chance to mourn the loss of this child. I'm going to see the doctor today to enquire about stress leave and I'm worried I may be denied due to lack confirmable hCG levels. how long do hCG levels stay in my body after I pregnancy of 3 weeks and 6 days after start of miscarrige?? Any and all info clarity on this would be greatly appreciated. Many thanks to all for your input into this matter.