Having an unbelievably stressful day

[Chocolatesgalore]

I'm having one of those days where I can't cope with anything. My laptop decided to break on me, so I'm no longer able to do any of my work, which is due today and not only that, my workload has also tripled within the last three months and we are a staff member down, so I'm only one working on four projects at the moment without any help.
I've also decided to quit smoking which I'm really struggling with and my dog is driving me absolutely crazy, as well as my life in general being a shambles. How does anyone cope with a really really stressful day? Because I'm really struggling to convey my emotions and not lash out.

Is the laptop provided to you by the company?

Immediately - can you take a break? Go outside and fast walk around the block to try to use up some adrenaline / cortisol and take a breath....

Then more practical stuff should seem easier. Break it down into what you can control, and what you can't.

Can you contact person who is expecting work and make sure deadlines are adjusted?
Can you access anything online if you can get to a library / borrow another laptop?
Can you book a meeting with a manager to discuss workload concerns - sort out some of the issues at source

It's not your problem you have an unrealistic workload - it's theirs. So push back your boundary.