Funny feeling - help me!

ok, lately i've been getting this funny feeling.

it comes on quickly like an attack.

it feels as if my stomach is clenching up and i feel sick. the world starts spinning, i can actually hear my breathing and i have to force myself to breath. it's a weird feeling and i have no idea what it is.

i'll have the sudden urge to scream, kick, shout... and kill anything. i start digging my nails into my skin because pain makes it stop.

i've had these random attacks all my life and they stopped when i started cutting last year - which is why i was so relucant to stop and i guess thats why i resort to pain when it happens.

once, when i was alone, to stop the attack i bit my hand - hard. i had puncture marks and i bleed. the funny feeling started dying down and i pulled at the roots of my hair. only when i slammed my head against the wall did it stop.

it's started to freak people out at school, because before the school year finished, it happened really badly at school. so, to stop it, i slammed my head repeatively into the wall.

i dunno whats wrong and i'm really confused...

eep! help me!