Estrogen Levels

I am currently 7dp5dt.  At 5dp5dt my estrogen came back at 162 and progesterone at 195.  My levels 3 days previous had been estrogen 2100 and progesterone 147.  Before I went in for my retrieval my estrogen was about 8000 then were worried about me hyperstimulating.  At the day of the transfer they had dropped to 2900.  Usually you would get a booster HCG then but they didn't want me to hyperstim.  So anyway, on 5dp5dt they had me do an HCG booster of 1500 units.  I went back in for blood 2 days later and my levels had dropped to 140 for estrogen and 147 for progesterone.  They had me do another HCG booster and are hoping that my estrogen comes back up( they said weren't worried about progesterone since it was so high).  My question is, if my levels are dropping then doesn't that mean I'm not pregnant?  Can a HCG booster really save a pregnancy?  What are your thougths about my levels dropping?