It's very common to have bleeding and cramping in the first weeks of pregnancy. Don't worry.
There is nothing you or a doctor can do to stop a miscarriage IF that's what's happening. It just means the egg didn't develop properly. Unfortunately all you can do is wait and see what happens. I'm sorry. It's a horrible situation to be in.
Unfortunately we cant do anything to help you and I'm not sure if you're religious or not but have faith GOD makes so many miracles happen I will be praying for your little one so that he/she can be okay I hope everything goes well for you and try not to do too much just try and rest :)