I had a miscarriage and D&C a few years ago, and it took months and medicine (can't remember the name, the med that causes ovulation) to sort of kick start my body into returning to normal. It's like it still thought I was pregnant with various pregnancy symptoms.... And because we were devastated by the loss, it didn't help that I kept thinking I was pregnant again.
I started tracking my basal body temperature and discovered I wasn't really ovulating despite a few weird periods (thus the meds). About 13 months later, I finally got pregnant again (naturally, no meds that month), and this time it "stuck." My 22 month old boy is the happy ending!
I know how hard losing a baby is--sometimes I think my body going a little haywire just mimicked my emotions--and it wasn't until I had dealt with the miscarriage completely emotionally that my body was able to handle another pregnancy.
That's just me though--good luck to you!