If the pedal got "weak" or "light", my guess is the CMC may be starting to fail. The CSC tends to fail suddenly, in which case the pedal falls to the floor with no pressure.
If it's difficult to put it into gear, then it may be a synchro issue.
It looks like you have a 2009, so it's probably time for some clutch work if nothing has been done recently. I'd take to a shop or dealer that you trust and get their opinion, especially if you're not going to fix the problem yourself.
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2011 370Z 6MT Sport Gun Metallic | ARC | CJM | Ecutek | FI | Fujimura | R2C | SPL | Stillen | TWM | Z1 | ZSpeed | |