PLEASE HELP!

So I went to my doctor today and got a positive urine test but then she did a blood test to do a quantitative count of HCG, it came back as 200 I think I'm 4w2d she seemed concerned and said its a bit low and said well test again Wednesday...I'm a wreck right now de said either it's really early, it's the bringing of a miscarriage or a possible ectopic pregnancy