Ttc after a mmc

A

I found out I had had a missed miscarriage on Friday. I was 12+6 but baby was found with no heart beat and measured at 9+4. I had an ERPC on Friday and was wondering if anyone knows when i’ll get a negative test as I took one today and it was as blazing positive as the one I took at 7 weeks pregnant, and also, when can I start ttc again? Thankyou for any advice x