Multiples or Molar pregnancy?

I am a bit afraid.  I found out I was pregnant on Thursday and went in for a quantitative hcg test on Friday and Monday.  Got the results today and my doctor wanted an ultrasound done right away.  Hcg levels were high - 572 on Friday and 2462 on Monday (quadrupled in a 72 hour period).  No bleeding or other pregnancy signs (except that I am a bit tired and have to pee all the time).  A bit of tenderness on my abdomen.  Uterus normal size.  Not ectopic, but doctor said it can be one of three things: normal healthy singleton baby, multiples, or molar pregnancy.  She saw a few cluster (not exactly clustered) of sacs that could be multiples, molar sacs, or just blood filled sacs of the egg trying to bury into the uterus (normal).  She thinks I am about 5 weeks but is too early to tell anything.  I go in for another ultrasound in 2 weeks and am going crazy.  Anyone with a molar pregnancy, help!  I also should note that I have a 13 month old, am breastfeeding still, and have not had a period since I was pregnant with him.  Back in March another doctor thought that my hormones were going crazy trying to get my period to start (my ovary was a bit swollen) but no egg was ever released.  I think my hormones have been on overload and going crazy since then trying to get me back on track.  Could this be why all this is happening?  Help!  I am literally going nuts!