Bleeding at 9 weeks

I have been diagnosed with a subchorionic hemorrhage about 4 weeks ago. Normally, I would spot brown blood. Yesterday, I shot some hoops with my husband, and went for a mile walk. I woke up to use the restroom, and wiped blood that was similar to my period blood. It has been 7 hours since the incident, and I am spotting brown blood. Prior to this episode, I was having strong nausea and breast pain accompanied by light headedness.

I fear this could be a miscarriage. Does anyone have any advise?