Pregnant again?!

I'm 3 days late with no bfp yet, after having had 3 miscarriages while ttc for the last (almost) 4 years. The OB said they could get me in next week but I hate waiting that long because we don't know what caused the previous miscarriages, but if it's something as simple as my hormone levels not rising enough, it could possibly be prevented if I went to the OB early enough... Blugh, my husband and I want a baby so badly, but I desparately do not want to have another miscarriage... the 3 I've had is already 3 too many...