My blood results

My doctor just called and said that everything came back perfectly fine. He said that he was really impressed with my numbers and felt very good about things. My beta level was 30,482....is it just me or does that sound extremely high for only being 5 weeks?!?! I asked him if he thought it could be twins and he said, "Well yeah it's a possibility but don't read too much into the number." EXCUSE ME!?!?!??!!?!?!!? I figured if there was more than one, we would have been able to tell by the unltrasound. Is that why he wants to see me next week for another ultrasound?? AHH!!!