J.D.
Beta is not progesterone. Beta is HCG level. This should double every 31 to 48 hours.
http://www.bobrow.net/kimberly/birth/hcglevels.html
If your progesterone level is 163, that is a good sign for your pregnancy. It is better to have a high progesterone than low. Progesterone levels vary from woman to woman and pregnancy to pregnancy. I wouldn't consider it a sign of anything bad or twins since it is so early in the pregnancy.