Subchorionic hematoma

I had my 8 week ultrasound yesterday. I was told I have a 1cm subchorionic hematoma but my doctor wouldn't really go into detail about it. I tried to ask a lot of questions and still just "look out for cramping or bleeding and if so, come in." I'm really worried. This is our second baby. Our son who is 8 is so excited. Should I be worried? I'm reading that a lot of people are put on bed rest or start bleeding which thankfully hasn't happened so far. What should I do?? Not getting answers is really upsetting me.