When i stand up fast I almost black out every time, and sometimes i get so close to blacking out that I stop being able to really hear well (my ears ring so loud it s difficult), and my tongue tingles. Also, why does my heart beat so hard? Sometimes at night I m trying to be really calm and relaxed to meditate and stuff and my heart is beating hard enough I can t relax. I try to slow my breathing and make it regular, but I can t because it makes my hear beat harder again. And sometimes my heart beats so I can hear it in my ears (which I don t think is that uncommon) and I can feel the blood pumping really hard in my head and my arms and legs, etc. idk if i explained that right... anyway, what is my condition? I do those blood checker machine things in walmart all the time! lol, they always say normal stuff though. Could it really be as serious as a mini stroke? Why does the blacking out (and things along with it) only happen when i stand up?