Renault Megane 2003 fault?

Hi, I have a 2003 megane 1.4 dynamique petrol. Have a couple of problems with the car;

1. A warning message comes up saying check injector when driving. When the messsage comes up it feels like the car has a turbo or gains extra bhp

2. The lights on the dash stay on when I get out and lock it

any help would be much appreciated