Baby after stillbirth

Patient: I lost my baby at 28 weeks and delivered her on the 20th of sep. I had bleeding for 2 weeks then it stopped my partner and i had unprotected sex on 3rd, 5th, 7th then i felt that i ovulated arounf the 8th. I had brown spotting on the 11th that continued for a week. 28 days after i gave birth i thought my period was starting i had cramps and a tiny bit of blood but then it stopped but the brown spotting has continued mostly only there when i wipe. We are wanting to have a bub asap. Im wondering what are my chances of being pregnant again already i have done 2 tests around the 28th day after birth that were neg. when will this spotting stop after birth