Low Levels

Had a blood test a couple days ago and have called to get the results. I should be about 6 weeks. They said everything was normal but that one level was a bit low and that I should make a non urgent appt with my doctor. I have made one for Friday which feels so far away. I am very worried that my HCG levels are going to be low (it could just be vitamin levels but I have a bad feeling). I know you can't tell anything definitive from a single HCG value but now I am preparing for the worst. Such an awful feeling to not know! Why can't they tell you stuff over the phone?!? I would rather be able to prepare myself. It's my bday too :(