"Open eyes meditation"

[Dreamwalker]

I meditated maybe just 10 times. By that i mean i seat with legs crossed and close my eyes. After third  meditation i just lied in bed and started focusing on a single imagined dot on my ceiling, the more i focus black sphere starts appearing and expanding, sometimes changing in black cloud-like shapes. The more i focus its like some black clouds but very tight ones start to fly around me it's like i can feel them like they will reach me they feel very light. I start feeling cold, get some weird feeling in my chest, my hart rate is speeding up and its like that black sphere is sending some waves in my head and when they reach me it starts buzzing in my ears, every time is louder and i have to stop because feel very exhausted. Last time i've done this i felt like my chest would explode i started to shake, couldn't control my legs, my eyes. Then i have those dreams where  i am paralyzed and my legs are in my usual meditating position, that sphere is in front of me and its moving to the right, then my legs start to levitate to vertical position then back down and up again it lasts for a short time then i wake up. Last night same thing my legs levitating but the sphere is very close to me but it has rays from it. What could this mean? It's like in a close eyes meditation when i am in complete darkness and i see these different shapes of black color. But what about this "open eye" meditation?