Producing milk?

So I had a missed miscarriage, baby died at 14 weeks but my body didn't notice until I was 18 weeks, somewhere around 15 weeks my boobs started leaking, now that the baby is out, they are still leaking everytime I don't wear a bra, the nurse told me to wear like a tight sport bra for 3 days and she said that it would go away, however I have been doing that for 2 weeks and when I try to nor wear it it start leaking again, is this normal? I've taken home pregnancy tests and they all come negative which means that hcg is gone so why am I still leaking? Has anyone gone trough that?