High HCG levels?

I went into a women's hospital today because I have not been feeling good at all. Tired, nausea, chest pains, shortness of breath, gassy, heart burn, weak, dizziness. Lots of cramps and lower back pain that literally feels like labor pains and brown discharge. They did a ultrasound and quantitative HCG count, which was over 300,000. Ultrasound showed a singleton pregnancy measuring at 8 weeks exactly and heart rate of 153, they also found a subchorionic hematoma. What I wanna know though is has anyone had a HCG level this high and should I be worried. I have not been able to be seen by an actual OB because all the appointments are backed up.