surprise pregnancy, low hcg

So I went to the ER with galbladder pain. While I was being triaged my urine sample came back positive for pregnancy. Blood test confirmed but my hcg was only 13. It would also have been the day of missed period with conception occurring 10 days prior. I'm scared to death and in limbo and they don't want to see me for another 2 weeks. Anyone have similar stories and what was the outcome?