Bottom line, if your not sure, you need to jack it up and get underneath for a look, or take to your local guy, and put it on a lift.

If it's just AC water, give your mechanic a tip, and drive it like you stole it.

Not to depress, but it could always be oil from leaky Value Covers, or that leaky Tranny plug.

Better to be safe, and nothing beats peace of mind...