I go out for a run most days, for the getting outside as much as the running. You feel connected to the world a little bit. So many symptoms of panic are the symptoms of running – racing heart, breathlessness. Weirdly, running has always been my calm place. It’s to do with controllable pain, a pain that you know can end by slowing down. There’s a sort of strange joy in that. If you’ve been through mental or physical pain you can’t control, there’s something comforting about knowing you’re in charge of the dial.

Weirdly, as I get older – I’m in my 40s now – I’m getting better about the thought of ageing. Research says people who worry most about getting older are younger. The thing I find hard about being a father is that your children are a measurement of time in front of you. My children are nine and 10 now, and on the cusp of becoming a different type of child.

The fear of ageing is also the fear of wasting time. I have to watch that with my work; that I make sure when I’m not working I’m enjoying the people I love, having good experiences and trying my hardest to escape those fears of the future or the nostalgia of the past.

Yesterday I was listening to songs from the 90s and getting all sorts of weird pangs. I listened to St Etienne and was nearly crying thinking about the times you can’t get back. People say music sends you back in time but it only sends you half way. It drives you into the past but you can’t get out of the car.

It’s getting on for 20 years since I had my first breakdown. I can still fall into bouts of anxiety but the difference is I’ve developed an inner therapist. When I’m ill, happiness is just normality. As a young man, I wanted everything loud and intense – spicy food and edgy movies – but now I appreciate neutrality and life on low-volume.

Notes on a Nervous Planet by Matt Haig is out now (£12.99, Canongate)