[pdonis]

> The two are distinct because the inflationary period is described as happening at a rate faster than the speed of light and the big bang is expansion constrained by this limit.

This is not correct. "Expanding faster than the speed of light" isn't really a good description of the expansion of the universe at any phase, but if you're going to use it, it can happen during all phases--in fact it's happening now relative to us for parts of the universe beyond the Hubble horizon.

The key difference in the inflation period was that all of the energy was in a single field, the inflaton field, whose properties caused exponential expansion of the universe with a very short time constant, so the universe "inflated" by a huge factor in a very small interval of time. At the end of inflation, all that energy got transferred to the Standard Model fields (quarks, leptons, and radiation), which don't have that property (although now the expansion is dominated by dark energy, which does have the "exponential expansion" property but with a much, much longer time constant so the expansion only accelerates very slowly).