Dodge neon 2005 sxt leak and freon smell?

i have a leak that feels like coolant or something dripping from the bottom of my car on the driver side. you only see it when my car remains idle for a while and then there is a streak of it as i drive off from park and after a couple secs it doesn't show any leak anymore. but always after it sits there idling. also when i turn on my ac i smell something like freon coming from the vents. (i feel i should let you know that i punctured a small hole in the penger side under the dash to the left of the air blower i was stapling something and i hit something behind the plastic and it was making a hissing noise for a while and stopped after a day. but i know it was pressure of some sort and it smelled like freon....what's back there and how severe is it? could you guys please answer both questions. thanks.