firework massive lag and crash

when i play the minecraft snapshot WITH TMI (toomanyitems) mod on and spanned me some creeper firework i lags a lot when using them and crashes when i lunched 5 to 10 arrows
PLEAS HELP ME :c

stats:
32 bits
grapichs: fancy
renderdistanse: medium
singleplayer ( old map fro 1.2.5 )

ps. sorry for the bad english D: