A key to lubrication of any aircraft engine is how soon an oil fog can
be established in a crankcase. This takes a while - especially if the
oil is thick, as the bearing journal clearances are not that great and
the amount of oil thrown from them is minimal given starting oil
viscosity and the comparatively low crankcase activity at low rpm.
Most of the oil flow generated by that fixed volume oil pump ends up
blowing over the relief valve and dropping directly back to the sump,
giving the oil little access to the heat of the engine pistons and
cylinder heads. There are no features on the rotating machinery that
will centrifugally splatter oil blobs onto the cam surfaces. They
have to depend on previous operation for lubrication until the fog
gets more generally developed.

Oil viscosity can easily vary over a 100:1 range between moderately
cold start and normal operating values. The leakage from a journal
bearing will correspond inversely as that viscosity and directly as
the cube of the bearing clearance - which is also compromised by the
differential thermal expansion of aluminum vs steel.

Remember it isn't the bearings - it is all the expensive surfaces in
your engine that are starved in a cold start. And the operating
profile is almost always a full takeoff power after only a few minutes
of operation.

I do agree though that the OP didn't do any substantial damage to his
engine since it had been run so recently and since it has
Continental's bottom-of-the-crankcase camshaft.