This started happening 2 days ago..

The engine seems like it decelerates faster when I let off the throttle. I know it isn't the wheels or brakes decelerating it because when I pull the clutch in the bike rolls really well..
The bike makes more noise. Like its pulling uphill all the time.
It also vibrates a LOT more than before, at anything over 2000 rpm..
The only mod that the bike has are a set of akrapovic sp cans, and no catalytic converters.
Before it didn't do these things.
Precisely 1 week ago I had the oil changed on the bike... 14000km
Anyone know what the problem might be? KEV?