Panicking; Something real going on?!

For the past two weeks I've had these off/on headaches that probably have to do with how much time I spend in front of electronics + stress. They never get to a severe level; in fact they're usually pretty mild but I have to be in a dark room during these headaches (makes sense if it's an ocular headache, right?). When I spend time away from the laptop for a day my symptoms go away, and sometimes I can go online for a long time after that with no negative effects; other times I can't. I keep thinking this has to be a brain tumor or some brain aneurysm that's yet to burst. This anxiety is most present when I'm trying to go to bed at night. I'm scared that I'm gonna pass in my sleep so I try to stay up as late as possible to avoid that.

Today I swear I had some hypoglycemic-like symptoms: My leg started twitching, I felt exhausted, and I was craving sugar. This convinced me that I had a brain tumor that caused my leg to twitch and caused this hypoglycemic symptoms. Maybe I have diabetes instead; that's certainly more preferable than a brain tumor.

Why do I have to be dealing with this? Why can't I just be a perfectly healthy 17-year-old and enjoy life?

I can only speak from experience but if you have headaches only when staring too much at a screen, it may have something to do with your eyesight.

My reason to suspect this is because of experience. My right eye cannot focus well, it is far sighted, so my left eye is strained by having to over-focus to make out a clear picture. Thus, my head starts hurting really bad at the end of a work day, where I've struggled to make out texts, images, signs, etc. The screen emits light/rays that can strain eyesight even more. I was prescribed with polycarbonate anti reflective lenses and it made the headache appear less frequent.

It is serious to think you have a brain tumor... I lost a relative to a brain tumor, and he suffered from severe migraines, which leave you in an unconscious state. If you're really concerned about having progressively intense headaches, you should talk to your primary care physician about them.

Edit: I cannot really diagnose you, since I have no right to do so, I could only guess the twitching and craving for sugar to be stress-related. Having a bad posture for too long (like crossing legs while on the computer) or not walking, exercising, made my legs lose sense for a short time. I constantly move now.

Also, anemia and hemoglobin shape problems could contribute to the headaches. I suffered from this three years ago. It corrected by eating better, high in fiber and iron. (Not that you may have it, but eating correctly almost always contributes to a better health.)