i can be perfectly fine, but when i lay on my stomach and if i like rest my head on my arm or even have my head up i just get the worst pain in my head like a headache just suddenly and i'll just hear a lot of rustling in my ears. i dont know why this happens? im only 18 and ive had bad headaches as far back as i can remember, seriously, but this laying down this has only been atleast about a year that i can recall. any ideas? :/

Maybe you should have an MRI on your neck. You could have a bulging disc in your neck, or something else that, when in that position, triggers a headache.