The loss of an early pregnancy is called a miscarriage, a sad event. The cause of a miscarriage is almost always chromosomal, something has gone wrong in early development. Usually when the egg is fertilized. So there is nothing you can do about it if you have a miscarriage, sports or physical exertion will not cause a miscarriage. You cannot prevent or stop the miscarriage.
If you have a miscarriage, it can be devastating. Sadness, disappointment, mourning and anger can alternate. This may all be there. Take the time to process this. Know that you can always call us, it is important to be able to speak about it. Also talk about it with your loved ones, it's nice to be able to talk to someone you trust.