When will I begin to miscarry?

Chloe • 2 angel babies 😇 😇 ❤️ 1 baby on the way 👶 💕
To cut a story short, I did a test and was 3-4 weeks pregnant (approx), started very light brown bleeding, passed a clot, the bleeding has stopped, it lasted 2-3 days, not enough to even wear a pad. Midwife did a test, it was negative. She said she was sorry and I miscarried. I did another test today, negative. Still have sore boobs, still feel sick, haven't bled.
If this is a miscarry, when will I expect to start bleeding? Is there more to come? I had slightly painful lower back pain last night, nothing since. Is there more to come? Will I begin to bleed more? 
There's a foul smell down there. :(