Two sacs but "low" HCG level

Mell
I went to the doctor, did an ultrasound and found 2 sacs at 5 weeks. They took my blood to check my HCG level. They expected it to be 20,000-30,000 because of my symptoms but it only came back at 9,000. I'm now VERY worried!! I go back next week to check for heartbeats. My pregnancy emotions are getting the best of me. Anyone else have multiples and not crazy high HCG levels?