Do women usually have symptoms or know they had a miscarriage or are having one?

I am speaking a little more on the 7-12 week span.

?2014-03-19T00:17:08Z

Symptoms of a miscarriage include vaginal bleeding that may be light or heavy, constant or irregular. Although bleeding is often the first sign of a miscarriage, first-trimester bleeding may also occur with a normal pregnancy. But bleeding with pain is a sign that miscarriage is more likely.
Pain. You may have pelvic cramps, belly pain, or a persistent, dull ache in your lower back. Pain may start a few hours to several days after bleeding has begun.
Blood clots or grayish (fetal) tissue passing from the vagina.

Emma2014-03-19T00:35:52Z

Everything as said by dollar bill also my friend had 5 miscarriages and said she knew something was wrong like inside she felt sad and just knew, a lot of people say they know the baby has died before the symptoms :( hope everything is ok :) xxx