Clutch slipping and then not?...oh oh

[Boxtaboy]

So was driving home from the gym and was at a stoplight on a steep hill. Park brake on, and drove off. Accelerated and noticed clutch burn smell and revs rise without that much accelerating. Clutch slippage. Kept driving and after a minute, no more slipping. Pushed pedal down in 4th gear and still no slipping. Car drives fine again. Is my clutch gone soon or just glazing of the clutch? Anyone have this happen on their 986? Oh, and car has 74k miles on it.