Hmm this isn't an easy question to answer.. the serious answer, (I say that cos most of my time I joke about everything) is that there is no black and white on this.. people are all different...and we know that not everyone likes pain... me, I hate it.. seriously.. I can take an enormous amount of pain but it completely turns me off.. I CAN administer pain and would and have to those who enjoy it.. but not everyone does...
Even within that there are degrees.. .of pain and tolerance.. I like SOME pain... but there's a fairly low line beyond which I don't enjoy it... some have higher levels of pain/enjoyment...
As to whether or even if they are separate.. to me they are.. definitely.. and I know this as a solid fact... I can do it but don't enjoy.. A friend however, told me that pain and pleasure sensors are very close within the brain.. perhaps even the same area... for her she loves pain... for me I don't....
So the non-conclusive answer is... everyone varies..
Benedict Arnold 