Why does lucid dreaming hurts my head in the process?

I've been practicing lucid dreams for quite a while now and I'm getting pretty good at it. While I may be having a lot more lucid dreams than usual, my control in the dreams are really minimal. Somehow I'm only limited to obliterating objects (melting it, bending/twisting, reducing it to ashes) and it's quite fun (:. I can last for a certain period of time but then when there's some sort of line that I'm trying to cross from that control, I get jarred back to reality.

But then again along the process, there's some sort of gravity radiating in my head and it's really heavy and it really hurts. Most notably when I'm trying to do things that I'm still yet to be capable of. Oh and my dreams sort of have these levels of dream sequences. I might have to think again everytime I seem to 'wake up'.

My question is, why does my head hurts? And why is my control limited to certain things?

Well, sorry, but I have no idea why your head hurts. About the control... My guess is that it's some kind of subconcious thing. I'm rarely able to control pretty much everything in LD, usually I have some limits also. Especially when I'm trying to change something many times. For example I once turned panda bear into brown bear, but failed miserably to change that into black bear later. I had no problem turning mammoth into small white rabbit though :D
How are you obliterating those objects? With hands, with some object or with mind? You should try to get magic wand or smth similar for control. For me it helped a lot. Gets some logic behind "magic" instead of just forcing it with your mind.

I merely just think of it. Say, I wanted an object to be melted. It does. But then again along the process it kind of hurts in my head. Not like a regular headache sort of pain, but it's sort of the pain you feel when you're tryna make yourself move under sleep paralysis. Hurts more when you're progressing in the dream, and when you're trying to do things that seems way beyond. Once the pain is sort of unbearable, I force myself to wake up. Considering it's a dream, I'd always think the possibilities are endless.

yes i kinda understand what you're talking about. i usually felt the burden in my head when i tried to do something purposely in my dream. even as simple as merely moving my hand and looking at it and try to feel it like in the real world is quite a pressure to the brain. and what i've concluded is that, in the process of learning to become lucid, we tried hard to become lucid and hence burden to our processing brain. and that pressure will shatter the stability of our dream and eventually be woken up.

this is why i'm thinking of opening another thread about the good and bad about being lucid in a dream, but since this thread is relevant, let me just state it here. my recent lucid put some pressure on me that i concerned too much that i've already been too long in a dream and forced myself to wake up, in reality i realized i only just slept for 2 hours, with no night sleep before that i should need 6-8 hours of a good sleep. otoh if i just linger in lucid dream without concerning how much time i've been sleeping, maybe i will sleep too long or will never wake up :D or will be late to work. and its like i never got a rest you see... before sleep i worked, and then when i sleep, i woke up again in my dream and processing stuffs, and then i woke up again to go to work. there's no rest (ie blank paused non lucid no dream sleep) in my brain, you got what i mean? so maybe i think i should not being lucid everytime, esp when i got really tired in my daily life. i think i will only want to become lucid if i have a good rest beforehand and just want to have a fun in the dreamworld.

Yeah i had my first lucid dream wich was about 1h 30min irl. and when i woke up there was pain in my right side of the pain and right eye had pain too. could it be that i stressed my brain too much? I remember when i found out that i was dreaming i immediatly tried to fly upwards and it worked although breaking window with thought or hand movement wich had antirush. I remember that when i found out i started doing stuff really quickly and if something wierd occured i knew i was in a dream. btw it wasn't quite stable, when teleporting i think i almost woke up ..