"Anxiety is one of the most common issues that people come in to see me about", says Dr Anna Waters.
She's a top psychologist who has helped international sports stars and performers cope with mental health issues.
"I'd say everybody's experienced some level of anxiety in their lives."
She tells Newsbeat there isn't a cure but there are things you can do to help if you're struggling.
"It's about first of all recognising you're anxious, and then looking at what's actually causing that anxiety. Everybody will feel anxious about different situations".
"I always ask clients to think of two questions, and that is 'in order to perform at your best, what does that actually look like?' and then 'what do you need to focus on to perform at your best?'"
She says it's important not to compare yourself to other people.
"That could be in an exam, or it could be going on a date.
"If you concentrate on being not the best, which means you're comparing yourself to other people, but actually being the best you can be in that particular situation, and what do you need to focus on to do that, that means your attention will be focused on the right things and things going positively".
Anxiety is often caused by things "outside your control", she adds.
"If you're a performer you may be going on stage and starting to think 'what if somebody boos? What if I forget my words?'.
"If somebody boos, does it actually matter? All you can do is concentrate on your own performance. Try and keep perspective on things".
And importantly, you should seek help if you are struggling.
"People can expect that the anxiety will go away, or that it will get better, or if they're about to perform, perhaps people will think 'I'm not going to think about my performance until I'm on stage because then I might feel anxious about it.'"
"But that can mean that when you get on stage you feel overwhelmed with those fears.
"Whereas if you actually start to identify them beforehand, then you can start to overcome those fears."
There's advice on how to cope with mental health issues, or help someone dealing with them, on the BBC Advice pages.