Beta Drama. Please help (cross post)

I have been in beta craziness for 2 weeks.

My LMP was June 12

July 7- Beta 31
July 10- Beta 49 (very concerned)
July 14 - Beta 89 (thought I was done; told to stop all meds)
July 17 - Beta 300 (no ectopic seen)
July 19 - Beta 600
July 22 - Beta 1900
July 24 - Beta 3139 (concerned because beta didn't double)

I have had no pregnancy symptoms.
Do you think it is a blighted ovum?
Why would the beta not double first week and then start doubling?
Is it of concern that it didn't double from July 22 to July 24 (today)? Any and all help would be greatly appreciated.

I'm 42. My fsh is 13-18