Headache when masturbating?

Ok. I've been having these for quite a while now. (about 7 years, I'm 17 now) Because I started masturbating about when I was 10 years old.

The problem is that sometimes(not all the time, keep that in mind) when I start masturbating I get a bad headache. I start getting the headache when I start rubbing my penis up and down. But when I stop rubbing my penis up and down my headache immediately starts diminishing and almost goes away. It is very weird.

My question is what could it be? What is causing this? Could it be serious?

P.S. Please don't tell me to go to the doctor because I have no money and no insurance.

Thank you.

-Guy with possibly dozens of diseases/disorders.

I forgot to say that it sucks.
It makes masturbating a torture when it is supposed to be a pleasure.
I have to stop masturbating or else I will get this horrible headache.

Also I want to mention that I have masturbated when I have the headache and want to say that immediately after I ejaculate the headache slowly starts diminishing and dissapears.

Please consider whether or not you have high blood pressure.
As you masturbate, your blood pressure will increase. If it's already high, you could have pain from the vessels in your head being under too much pressure.
Monitor your blood pressure routinely.

Too much dry weed or too many cigarettes is my guess. If you have a headache, a rise in blood pressure is almost sure to make it worse. Any sudden, vigorous exercise will. Drink water. Take a long walk with your water to get your fluids moving. Continue masturbation.

Maybe ur gettin a headache cuz u feel like ur doin something wrong. Like those guys that used to go blind from masterbating. (or is that just something ppl used to tell their kids so they wouldnt do it?)

Ok, some of the causes are due to muscle contractions in the hand and the lower abdomen. I believe because the contraction is so intense that those muscles require more oxygen and therefore strip those oxygen from other areas such as the brain to satisfy their need to supply the cells with the oxygen. The brain when lacks oxygen may leads to comas or periodic headaches. Do what you have to do but do it within consideration. Good luck.

Constant orgasms tend to give some people headaches ; it is possible that you are experiencing orgasmic headaches..lol..sounds weird but true , but you need to really be open to your physician to find out about the specific reason....It is definitely from muscle contractions. Believe it or not , mastubation is a work-out .If you masturbate multiple times in rapid succession , boy you are forever doomed...take it easy , reduce your sessions by twice a day if they used to be 4 times a day ,(technically by half)...and stop masturbating when you start to get a headache.

Have you ever hung upside down from a tree or someother thing and gotten a headache? It's kinda the same thing except backwards. When you hang upside down you get too much blood flowing to your head and therefore it begins to hurt. When you're masturbating the blood all rushes to your penis so quickly that it can make you get a headache or lightheaded b/c there isn't enough blood flowing to your brain, that's why people say that when guys are horny they think with the wrong head since all the blood is there. The fact that your headache goes away when you stop or once you ejaculate further explains that it's the lack of blood to your brain. Most times it happens the other way around, once you ejaculate you get the headache since all the blood starts rushing to your head again, I guess you just work a little backwards.