[TheOtherHobbes]

Spacetime itself was infinitely small, so not necessarily.

We don't know anything at all about the physics of infinitely small spacetimes, because we don't have a fundamental physics of spacetime at all.

GR is a descriptive approximation of the behaviour of spacetime, but says nothing about the fundamentals that generate that behaviour.

[Rarebox]

Exactly. It could even be turtles all the way down, with new building blocks of physics becoming relevant as we go smaller and smaller (and back in time).