Can hcg levels indicate twins?

I found out I was pregnant at 10 dpo, but by 15 dpo I was having some spotting. Because this is my first pregnancy they wanted to do an hcg and type and screen (i had no blood type on file). My first value at 15 dpo was 587. Today, 72 hours later they collected a second hcg which came back at 2148. That seems like one heck of a jump if hcg is supposed to only double every 48-72 hours. Could this indicate I am pregnant with multiples?