Brake Trouble Help

[MugenNeuspeed]

Alright, I recently decided to go into my 93 240 and fix my brakes ever since I got into a minor fender bender and it cost me 300 bucks so that it wouldn't have to be reported to insurance.anyways my rear brakes were shot, I replaced them, and as I went to bleed the brakes, no fluid came out except a little!I went to bleed the front and oil came out like normal!What can be the problemMaster cylinder?I doubt its clogged brake lines but you never know right?any inputI am so dismayed, I just bought the car, and if I knew about this crap it would have saved me 300 bucks