Just had new cambelt and water pump fitted but now I'm having some wired issues

1: The car doesn't start on first try unless I give it a bit of gas then it picks up?!
2: While driving when I come to a stop the car idles erratically dropping then going up, it does this a few times before settling?!
Probably nothing to do with the new belt and pump but thought I would mention it just in case.
Any help would be great as it's a massive pain when I forget to put my foot down to start it and also well embarrassing in a packed petrol station when the car don't start and gives off a massive starter motor scream just to draw even more attention

Oh one more thing on VAGCOM it gives back "engine coolant sensor" Intermittent nothing else?!