Hi, I have a situation that is really confusing me and i'm seeking help please-

I had and IVF treatment and 3 eggs were transferred back 2 weeks ago... all went well till day 9 when I started to experience light bleeding... the following the day it became heavier (period like with blood clots and all) I called the doctor office and the assistant advised me to have a blood test although it's early... I did and it came positive and the hormone level was 12 (HCG test)... the bleeding continued and still have it till date but it's much lighter that it was... I had my second blood test today and was informed that I'm pregnant and the hormone level is 112 which is excellent according to the doctor... The doctor said when I asked him about the situation that it's normal and maybe because I had 3 eggs transferred it could be that one or two of these eggs dropped causing this bleeding and I shouldn't worry about it... but I am as I read many stories on the net ending by miscarrage... can anyone advise me or share with me any valuable information in this regard?

Thank you,