I was off sick for 8 weeks due to anxiety a few years ago. It had been building for a long time but I kept going in.
I was constantly run down, cold after cold after cold, struggled to get out of bed, struggled to make decisions about mundane everyday tasks. My anxiety was sky high, I'd worry constantly about work, did I document something, did I do everything I could, did I come across well, were people talking about my practice, did I handle something the right way.
I went to work one day on a few hours sleep having been up all night with the kids and with a terrible throat infection but I had to go as HR would have called a meeting due to sick time (see multiple colds).
I was sent back home almost instantly, was standing in the changing room and another manager asked why I was leaving - I said about the throat infection, the two hours sleep and that I wasn't fit to be at work. They replied there were plenty of other patients I could be working with and I could stay clear of the immunocompromised ones. I worked in ICU.
I left that day and phoned the GP in the car park, went back two months later.
I was juggling so much at the time and the only thing I had control over was going to work, I had to take it out of the equation to sort out my mental health and my home life.
I wouldn't hesitate now to go off again if I ever had to, I recognise the signs now and I wouldn't ever try to push myself through it.