Gender Roles are Negotiable. Sometimes the woman wants to pay for a night out -- and sometimes it's the guy who stays home to raise the children. This means your old fashioned dating rules will have to be a little more flexible nowadays... and that is a wonderful thing.
Roughly: HCG drops at roughly the same rate it rises when a pregnancy fails, so an hCG of 400 can easily take 30 days to drop down to 10 or less. If you are concerned you should ask your doctor (or a doctor) to check a quant hCG again. ...
However, if you were just a few weeks into your pregnancy when you miscarried, you might be pregnant again. Typically, it only takes 19 days to a month for your hCG levels to disappear completely and provide you with a negative pregnancy test result.