I'm very sorry to hear about your miscarriage. I'm afraid you just have to take it one day at a time. If you feel sad, allow yourself to feel that way, have a cry if you want to. Eventually some of the day, or even for a whole day, you will feel better and start to enjoy your normal life again. It is hard, very hard, and it takes time. You'll always wonder what if, and you never forget the miscarriage, but in a little while you'll hopefully be ready to move forward and start thinking of the future.
The feelings are just so horrible and raw at first, the only thing to do is take care of yourself and hopefully have good support from your partner and family. If it is really getting too much, and you are having difficulty coping with day to day life and problems sleeping after a few weeks have passed, then it's time to see a doctor for some professional advice about depression and counselling.
Statistics show that a very high number of women suffer symptoms of depression in the first six months after a miscarriage. For most of us, it passes in time, but some do need a little bit of extra help.