1999 toyota corolla ce getting misfire in #2 sparkplug

Daughter told me car wasn't running right. I saw the check engine and it was saying misfire and #2 spark plug. i took the spark plug wire off and it seemed that it was full of radiator coolant. I'm not really seeing how this can happen. I blew all the coolant out with compressed air and dried out the wire and plugged it all back in. Seems ok now, the cyclinder is firing again. Do i have a slow leak on a head gasket? i'm just concerned. Am i going to send this car off to the corolla graveyard?