Exhaust Emissions/EML Light!!!

Hi, I have an astra coupe turbo and just had the cam belt and water pump done at Vauxhall last Wednesday.

The car was fine for a couple days but now the Exhaust Emissions light {one that looks like an engine, NOT the car & spanner} is flashing, then stays on and the car goes into limp mode! juddering and jerking.

Do you think this could be down to something Vauxhall did or has something gone?

I'm gonna take it into to them to hook it up to the tech2 and find the fault code but just thought id check before forking out around £50 for a diagnostics check.

Any help would be appreciated.