Yes i think I am playing it loud, but I think it should sound loud or not? In this etude, it is almost always "forte" and if I play it "piano" it loses the revolutionary spirit, or not?
So, sorry for getting back to you a bit late.
Here is what you're gonna do:
At forte, you're gonna play the left hand softly with the damper pedal down. You will CRANK UP THE RIGHT HAND- Chopin was an opera lover, and he was always inspired by the SOPRANO voice. Most of his works feature the upper register as melody- REVOLUTIONARY INCLUDED.
Trust me, when you get the "C - D- Eb Eb" motif in your face, it sounds LOUD.
At piano, you're gonna play the left thand softly with the damper pedal down.
HOWEVER, you will perhaps experiment with different depths of the pedal- by reducing sustain, there is less sound lingering around, which helps things sound softer.
You will play the right hand softly- barely enough juice to be heard over the left hand; something that isn't terribly hard because of the register difference. (Someone like Rachmaninoff likes to embed the melody in the same register as the accompanimental notes, and it requires musical knowledge and CAREFUL balancing to pull off; not really the case with most of Chopin, this work included)
Now, to help emphasize the contrast, you're gonna use the UNA CORDA PEDAL- the leftmost pedal on the instrument.
So, in summary:
1. Always play the left hand softly.
2. Dynamic contrast is done primarily with the right hand and the una corda pedal (i.e. use the pedal to play softer at piano).
3. Experiement with different depths of the damper pedal at softer sections; remember, less sustain = less sound lingering around. (On this note, when you listen to Wagner's Tannhauser overture, do you know why the trombones sound so damn loud? It's partially because the trombone players are sustaining every note to the full value. Here, we're using an opposite idea of that approach to help things sound softer).
Oh wait, everything starts tensing up around the middle section eh?
The thing about the middle section, starting with 1st inversion G# minor chord on the right hand, is that your pinky and your ring finger are leading. Try NOT to drag your arm around to facilitate the weak fingers; rather, "step" with the fingers while letting the wrist and the arm naturally follow though.