brown spotting

My doctor instructed me to go to the ER for some light brown spotting. After 5 hours we learned hcg levels are at 2400, cervix is good and closed, i have bacterial vaginosis, and i am measuring at exactly 6 weeks and 0 days. They could not find a heartbeat but stated it may be due to the fact that im just not far enough along. Super nervous and anxious now!! Especially after they said, "any bleeding is a threatened abortion". Also worried because ive had more period style cramps today than before. Has anyone experienced a situation line this with a good outcome? Thanks in advance ladies!