S-Mode and gear indicator going out, lagging acceleration

[Uxi]

Put this in general and nothing.

Just recently, S-mode light started going out. Before that, something is "lagging" where I'll have the pedal down hear the engine revving but then the tach will jump from 3000-5000 then the gear indicator and s-mode light will go out. There isn't an S-mode warning until I hit the s-mode button.

After that, seems to rev normally but still feels and sounds a bit... off. Almost sounds like the engine is higher pitch if that makes sense. Or maybe louder.
I'm not getting the 'lag' after that, but it does appear that there is little to no acceleration before 3000 rpm that I don't think I've noticed before.

If I turn the car off it will come back with no warnings. Brake fluid seems normal. Sounds like a bad sensor or something else?

Drove a day with S-mode off and seemed better but still louder. Now it did the lagging from 3500 to 4500 again and the gear shift with S-mode off and the gear shift indicator went out. Think my clutch is slipping? Gonna take it to a mechanic tomorrow.