Charli XCX has been “feeling quite low”. The 29-year-old singer admitted her mental health has declined in recent months, prompting her to take a step back from social media because she was struggling to handle criticism of her new music. Speaking to the new issue of Rolling Stone UK, she said: “I’ve been feeling quite low throughout 2022 to be honest. I feel like my mental health has really taken a toll, and for some reason I just couldn’t really handle the negative comments that I was reading, particularly about music and my latest song ‘Beg For You’, which was actually beginning to do quite…