Hi.
My opinion is that the three things are separate ... that all three can be arousing but that bondage is the one that (I think) this site is about because it's more psychological. and at the same time the control thing (or loss of control thing) makes you very aware of both the sexual and non-sexual parts of your responses.
Not into pain but a lot of people here seem to be; same with humiliation. but there are lots of combinations here.

... my 2 cents.