PhilK:
For me, humiliation comes around midway along a scale running from embarrassment to degradation.
Since most of the stories I write feature spankers who are at least fond of their spankees, I don't generally describe the victims as being "humiliated," because I do consider that term to be rather close to "degraded."
"Extremely embarrassed" and "humbled," however, are feelings that I greatly enjoy a spanking recipient to experience since they should be part of serious corporal correction, and the former one often a desired aspect of undergoing even a fun/playful spanking...

--C.K.