Two painful m/c and no children.... :(

My husband and I have been TTC for about 4 years now. Very early on I had my first m/c. I started my period on exactly the right day I should have and it kept going and going and going. Ususally it lasts 4-5 days but at 8 days I was sooooo exhausted and started to worry that I had a serious medical problem. So on day 11 I saw my doctor and he tested me and told me that I was having a m/c. It was the last thing I had expected to hear, I had never even thought about the possiblity of that being why i had been bleeding so long. I was crushed! I climbed into my bed and cried for days and eventually ended up in the hospital because my cramping became so intense I thought I would die. I was very very dehydrated and had to stay off work for a few days. Then about a year later I just knew with everything inside me that I was pregnant so I went to the doctor and yahoo positive. I can't tell you how happy i was and how paranoid I was that it would happen again. Well about a week and a half later I had some cramp-like pain and ended up in the hospital thinking I was constipated (sorry). They did a blood test and yep I was having another m/c. I had to stay overnight at the hospital so that they could continue to do more bloodwork and confirm that the number was for sure dropping. They were they worst things that ever happened to me and the doctors say 'well at least we know you can concieve'! Well now I feel gunshy and really want a baby but so afraid that it will happen again and again. How much can one person take? Now two more years and nothing. This sucks.