I to have a few questions. Does it typically end in orgasm or not?

Blood flow increases to your brain as well. So headaches or nausea are not unheard of after sex. Orgasm is kind of a requirement to get the headaches and nausea to go away. As blood flow gathers it takes orgasm to release that blood flow. It will release on it's own but is considerably slower w/ out orgasm, so headache and nausea will be worse w/ out orgasm.

Just curious if orgasm or lack of orgasm is the issue. You didn't make mention of your age. It could be health related. High blood pressure maybe. I agree w/ skipper....toys, past abuse, does this happen w/ a partner or just alone?

Hope we can help you get to the bottom of this. Good luck until then.