EvolutionVIII

I have a problem with my 98 rb25 s14. About a week ago when I pushed the clutch in i heard a loud popping noise coming from somewhere under the car. It sounded like something was getting caught and not allowing the clutch to disengage unless i pushed on it really hard, but still happened whether the car was on or off. The noise would only happen sometimes so I thought nothing of it. It got worse and worse though to the point where it happens every time now and seems to only happen after the car is warmed up. The more i drive it, the harder it is to push the clutch. Yesterday after driving it for a little, it was extremely hard to push the clutch in and it actually wouldnt go into gear. I turned the car off and when i tried to start it, it wouldnt start because the clutch wasnt hitting the button behind the pedal to start the car. It still works though if i push it by hand. The clutch pedal was also not coming up all the way so I bled it today hoping it would help but it didnt and the problem still occurs. After letting it sit for a few minutes it gets better but after driving it, it gets worse and worse. Any guesses on what it could be? The popping noise seems to be coming from the clutch slave or around that area. Think I just need to replace the clutch slave cylinder? Any help on this would be much appreciated because the more i drive it, the worse it gets but I need a car to get to work!! Thanks guys!