after miscarriage how long till I ovulate


I went and got blood work my levels on the 22 was 420. then 27 they was at 70. doctor said he say they should go down at least 20 a day he said I should have a negitave preg. test next Monday which I normally don't wish for my uterus is healthy and said I can get try to conceive as soon as I'm ready. I read your really fertile right after miscarriage before your period . is this true my period should come next week but we have already had sex and and got back at this try again thing. but when will my body be able to get pregnant doctor said not till my levels are at zero but how many women ovulated before there period I'm just confused he said not to waste money on ovulation test that there about a week off .it be to late