GMC Repair: Buick Century Limited 1990 Brake problem, rear brakes, buick century

Question
Dear Pete
I am driving a 1990 Buick Century Limited. This car is in good condition, but I have been having brake problems lately. I had pads and shoes replaced not too long ago, (3 months)  and found that they had a very hard time adjusting the rear brakes so they felt comfortable, and not like they were going to lock as soon as I touched them. Finally they felt good.
Tonight as I got in my car to return home with groceries, I approaced a STOP sign, when I touched my brake pedal,  I heard a funny squeal, and then kind of a pop.  The pedal went all the way to the floor!!   I was able to get the car home,  had to brake slowly and  put the pedal all the way in order to stop.
I am a woman alone, and I would LOVE to have some idea on what this problem could be before going to the mechanic. If it is something too expensive, then I will have to wait awhile before a repair, but if it is just a line, ( though I saw no fluid on the ground, and I did look)   then I could repair it now.
Anyway, I have probably gone on too long. I would apprecaite any advice you could give me. Thanks so very much.  Peggy

Answer
hello peggy
i belive the shop who is working on your car is not doing thire job the right way . if you heard a pop in the brakes then it would be the hard ware in the back drums bring it to another shop . and tell them what you told me .

good luck tou u hun and u have a pretty name pete