Subchorionic Hematoma help

Had some bleeding today, just brown spotting and a little cramping. My OBGYN had me come in for an ultrasound, baby is measuring perfect at 6w3d. HR is 122. But he noticed a subchorionic hematoma and diagnosed me with a threatened miscarriage. I am on light duty and no sex with possible bed rest if bleeding gets worse or turns red. So my question is would you be worried? I know it is out of my hands but anyone experience this. If so did you have a healthy pregnancy? They're rechecking my ultrasound next week to see if it goes away...but any advice will help!