[Brian R.]

Yes, you may loose your brakes. Get it fixed as soon as you can. You are leaking this fluid from somewhere and if you can't see it, then you can't fix it. If you are inclined, take off the wheels and drums on the back and see if there is brake fluid in the cylinders behind the dust shields or on the cylinders themselves. The front discs are harder to look at and inspect directly in the cylinders. Take off the calipers and the linings and see if there is any fluid on the pistons where you can see. All of these parts should be dry as a bone.

Make sure all the bleed fittings are snug on the wheel cylinders.

If you can't find anything, bring it to a shop you trust and have them look at it. At this point, it may be the master cylinder leaking. May be other things, but I am not well enough aquainted with brakes to give more help.

This is too important to dick around with it. Get it fixed.