Bit of advice on the hcg hormone

So I had my d+c on Friday after a scan on Thursday to say my babies had died on the Wednesday! Pain stopped yesterday and I didn't bleed but the spotting discharge or whatever it was stopped Friday night. How long should I expect until in get a negative test? The Dr won't do bloods or anything but going by my internet cheapie test it was about half the faintness of the control line (does this even make any sense) xxxxxxx