How To Get Rid Of Panic Attack?

I am 21 and its my first time smoking indica weed. about 15 minutes after i smoked it i started getting a panic attack and feels like i am losing conscious. I tried to relax and closed my eyes but suddenly everything started fading away and it feels like my heart i going to stop beating and losing conscious. I don t know if this feeling is passing out or going to sleep, but i freaked out and fought out of it to regain consciousness. Later i went to bed but just laid there and too afraid to sleep. Every few minutes while laying down i get a weird sensation going through my body. If i resist that sensation and fight it nothing happens, but since the feeling keeps happening every few minutes i tested to see what happens if i do nothing. Then when the sensation occurred again, i didn t resist, when this happened it seems like my mind is sucked into a black hole and losing consciousness, i couldn t move any part of my body and couldn t breathe. it lasted for 10 secs until i desperately tried to regain movement. Could this be some sort of stroke or sleep paralyis (i was still widely awake)? it is worrying me all week because i m afraid it will happen again. I went to emergency room and they tested my blood pressure and said i was fine. I am just worried about that weird sensation that feels like i am going out of conscious and cannot breathe of move any parts of my body.