Hi Rcgarcia, I doubt that anyone would be able to give you a satisfying answer, no pun intended
When we orgasm, our brains release oxytocin, which is a very "expensive" brain chemical (neurotransmitter). It is called the "love hormone" and it is linked to feelings of love and bonding. From what you said (I have no libido, but I feel a strong urge to orgasm), I assume that you are feeling low, tired, or substandard and need to orgasm to modulate this feeling. If you ever get hooked on porn, it becomes your way to regulate and modulate a lot of states of body and mind.
I am curious though, what do you think is the reason for this to happen (experiencing the need to orgasm, but having no libido)? You do not need to answer.