Try this:
Code:
on *:TEXT:!testing:#: {
  if (%TimerTest == $null) {
    set -u10 %TimerTest on
    /timer1 1 10 /echo -a Cooldown over
    /timer2 1 10  msg $chan Command can be used again
  }
  else if (%TimerTest == on) {
    msg $chan Cooldown!
  }
}

Here is my multi channel bot smile https://github.com/zapdos26/mIRC-Twitchbot-Windows