So I was 4 weeks on the dot Friday and got my HCG drawn. It was 22. Everything I see on the net says the average # for HCG at that many weeks is 21. The nure this am on the phone said it was very low and would probably end in a MC. I got another leverl deawn this morning and my boobs are hurting more and more. Has anyone else had a "low" number? And why would the average be 21 but I am really low? I am so confused and kind of freeking out.