Brake fluid leak??

[Parva]

Got home this afternoon to find (what I think is) brake fluid appearing under the left [rear] side of my '94 E320 Cabriolet. Specifically, the accumulation of maybe an ounce of [red] fluid is on the bottom moulding in front of the driver's side rear wheel well, just behind the jack insert cover. And, there's a splatter pattern underneath--some on the muffler, some forward of the wheel on the undercarrage.

'Sides goin' to my mechanic 1st thing Monday AM, any chance there's anything I can do about it any sooner?

Advice, warnings etc will all be appreciated!