How can I make myself finish?

You don't say what your technique is, but it maybe that direct clitoral stimulation is too much. If so, maybe rather than stopping, you move off the clitoral head and move to the shaft or between your labia majora and minora. But ensure you have plenty of lubrication. You could try massaging your g-spot or the clitoral crura ('legs') from inside your vagina. However, if an intact hymen is important to you, that might not be a viable option.

I hope this helps as a start. If more explanation is needed, please ask.

Okay, so like, I basically just rub the top of my clit until I feel this amazing build up that feels as if I just need to relax and let free -if that makes any sense- but then my whole lower body tenses up and I try to fight through it, and the times I think I do brings me to a calmer place and makes it too painful to continue. I still don't believe I've finished though. I don't feel all the fireworks most say or that I've released anything. I feels build up, then become really really tense, then pretty much nothing.

What you describe does make sense, and if you feel you haven't finished, you most likely haven't. The way different people describe their orgasm will vary (as will the feeling of the orgasm described) but there would typically be a release.
What I suggested was happening seems to be the case. So I think moving off the "top of my clit" to a nearby area for a time seems a solution. Have you tried my suggestion, or do I need to explain in less technical terms?
By "the top of my clit" did you mean the head (glans) or the shaft?
Also is there anything that might psychologically affect your experience? Are there cultural or religious implications regarding your masturbation? Have you had any traumatic sexual experience? Can you tell me how old you are and whereabouts you live? Do you understand the terms I have used?
I hope this helps a bit more. Again, if you need more detail or explanation of what I have said, please ask.

Is it possible to be a person who just doesn't have the above and beyond feeling during orgasm? I mean. I'm okay with what happens. It feels great and if I try to keep going it hurts. My boyfriend really wants me to finish. I never thought about finishing really until him. He's why I tried to touch myself and get a reaction going. But, maybe what happens is all that will happen. Could that be the case?

Yes it is possible "to be a person who just doesn't have the above and beyond feeling during orgasm", and experiences vary from person to person and sometimes at different stages in life. Also the 'quality' of orgasm can vary from time to time. But that doesn't mean that there is not more potential. But chasing after a greater experience sometimes is counter-productive. Remember you are not just a body that automatically responds to the 'flick of a switch'. You are body, soul and spirit all under the influence of your brain - often sub-consciously

You say "I'm okay with what happens" but you also said earlier "it's ... too intense for me to finish the job" and "I still don't believe I've finished". So the indication is that there is more to come.

As you say "My boyfriend really wants me to finish", it could be the pressure from his is actually holing you back. It also depends why he wants you to finish. Is it for his satisfaction or yours?

When you say "I never thought about finishing really until him", do you mean you never thought about 'masturbating' or thinking about the actual 'finishing', because you then say "He's why I tried to touch myself and get a reaction going".

You ask whether "maybe what happens is all that will happen". I don't believe that that need be the case. However, I have asked several questions to enable me to help, but you have not answered them!

Perhaps you don't want to say too much in public, so you could register and answer privately if that helps.