Hematoma next to embryo

I am at 8 weeks 3 days and had my third ultrasound today. Pregnancy is progressing well, baby had a strong heartbeat, however, Dr pointed out a small pocket of blood next to the baby which he said could potentially cause a miscarriage (according to him about 15% chance). He also advised to take it really easy, no intercourse and no excersize, which will be very difficult for me as I am very active and used to exercising daily. This obviously has me very concerned and anxious. Dr. said that eventually if all goes well and the baby grows, the blood will either come out or be absorbed into my body. Has anyone else had this issue? Any tips on how to deal with anxiety been appointments?
Thank you!