Anyone have a similar experience

LA
After 3 chemical pregnancies I got another positive pregnancy test this Wednesday but once again my numbers looked low. 
My HCG was at an 8 so my nurse said a miscarriage was likely coming soon. But yesterday she called and said my number shot up to a 69 in less than 48 hours!
My progesterone is a 14. 
Anyone ever have numbers that shot up like this??