Enough is already enough, because of the simple fact that you should never push through any tension, pain or cramping in any part of the body while playing. Piano playing should never hurt, or cause cramps, fatigue or even tightness, regardless if you are playing Rach 3 or Twinkle twinkle little star. If you keep practising this way, you will just continue ingraining these tense habits, and they will be harder to get rid of (and if you plan on playing Rach 3 eventually, you'll want to get rid of them!)
Regardless if you continue practising Rach or something else, I encourage you to always focus on always allowing fingers, wrists, elbows and shoulders to be completely supple and free during playing (not floppy dead, but free).