Did somebody slip something nasty tasting into Louis Walsh's water this weekend? For some reason, the normally jovial judge was in a very feisty mood, and Simon, Dermot, the studio audience and even the Prime Minister felt his wrath. Louis faced a telling-off from Simon Cowell on Saturday, after he accused the PM of having "no taste" in music because he doesn't like John and Edward. A shocked Simon said sternly, "Tonight you have offended our Prime Minister and the British public. I think you should apologise." It didn't stop there, either. Later during the evening Louis and Dermot started sniping at each other after the X Factor host stuck up for Joe McElderry, prompting Louis to snap at him, "Dermot you are a presenter, I am a judge." Last night Louis lost his temper yet again when the studio audience booed Jedward, and in this clip you can see him swing round in his chair and throw a V-sign at the crowd. Naughty! There's no denying it's been a tense few days on The X Factor, but it's clearly getting to Louis more than the others. I think we may all be forgetting that it's just a TV show... What do you think of Louis' actions this weekend?