This is where I distinguish between faculties and impulses. I think that biologically it's a difference between serotonin and dopamine if I understand it correctly. I've been trying to clarify this for myself and I think it's an important detail although I may be in left field.
All pleasures are good, all pains are bad. These are faculties. But some desires are natural, some vain, some needed for life or for well being or other reasons. These are impulses, as I've been thinking of them. The removal of pain is a pleasure due to their dichotomous relationship. But the desire to remove pain might be pleasurable or it might not be.
Quote"You have to tell me if your reaction to that desire itself is pleasure or pain. Why are you pursuing it? Because the consequence of that desire leads to more pleasure than pain."
Bingo! It's not the desire itself that's a pleasure or pain, it's your reactions to it and to the consequences of it.