HCG Levels

I know this is probably impossible and just a miscarriage but... I found out this past Tuesday I was pregnant, completely shocked had no clue because this said day was actually suppose to be my ovulation day but my mom made me test because I was complaining of dull pelvic pain (nothing severe) to my surprise it and 50 more were positive I'm a nurse at a clinic and was at work when I found out so we immediately done blood work due to me spotting light pink my levels were 330 we repeated then on Thursday and they were 132... called the OB that I plan on using and she ordered more blood work for that next day and wants to see me this upcoming Wednesday. My levels today however must still be above 25-50 because I'm still receiving pregnant on clear blue digital which I've read must have at least 50... so my question is, has anyone had their HCG numbers drop then go on to have a successful pregnancy? Oh and I'm no longer spotting or anything and the pelvic pain stopped the day I found out I was pregnant after having a BM.