Sorry you are going through this. I also miscarried at 11 weeks with baby measuring 7.5-8 weeks. I have also miscarried at 8 weeks with no fetus (its called a missed abortion, there is a sac but no baby), and my first miscarriage at 4 weeks. I have never done the D&C. If you have started bleeding the process won't take too long until you pass the yolk sac (a few days or a week). However what can take long is when the baby had died, but you are not yet bleeding naturally. Thats what can take 4 weeks. If you have any natural bleeding it won't be long. I passed mine before my scheduled D&C. More on that later.
My most recent miscarriage we detected at 7.5 weeks but I went to 9 insisting on one more ultrasound to find the fetus. When it was not there and i was not bleeding naturally, my dr. gave me pills that I inserted vaginally to start the process. The bleeding started a few hours later but I had to take the dose 3 times over a course of 6 days before the yolk sac passed. I felt no more pain than a regular period, but because my previous miscarriage was a bit of a production, I had to have my SIL and MIL over to care for my children because I just didn't know. I had heard you can be sick in bed with the meds, but that just wasn't the case for me. I did light housework the whole time.
I can see where D & C's are preferred for working mothers. Natural miscarriages are unpredictable , you have to stay home, and it can go on a good week of active bleeding and passing large clots and tissue.
That said, I'm very glad to have passed mine naturally. I notice a lot of women struggling to move on from the loss of miscarriage and it seems to me the ones who struggle the most are the ones who had the D&C. I think the D&C does not lend itself well to the grieving process. More on that latter.
My first miscarriage at 11 weeks was painful. I don't want to lie. I cramped up pretty good, and for about 10 minutes I would say I went through a micro mini child birth to pass the sac. I found out later that I had passed a sac in tact (which is very rare), this made me need to dilate more , which is why it was painful. At the time it was freighting and I'm so thankful my MIL had come out that day, I would not have wanted to be alone in the house. Looking back I know for me the natural miscarriage was cathartic and helpful to my grief. The physical pain mirrored my emotional pain. Going through the pain released my feelings. I suspect that women who have the D&C don't experience this release. After the sac passed there was bleeding for a week or two after, but nothing painful. Somehow my grief followed my blood flow. That may sound strange, but when the bleeding stopped, I stopped grieving so badly. It was like a cue.
This is going to be TMI for some so don't read if you are squeamish. I'm also thankful I got to go through the products of conception. I cut open the sac and looked inside. The baby was no longer in there. I also believe I saw the baby, though it was not much to look at. They will not show you any baby or products of conception with a D&C. I can't explain it, but I just needed to see. It was confirmation that the pregnancy was real, that my pain and loss were real.
If you are not bleeding yet, ask your dr. about medications that can start the process. If you have family support and a grandma who can come watch your kids, I recommend natural miscarriage.