Top tips: figure out how to do real deep breathing, it really works. Drink water. Make sure you've eaten. Do yoga (even if you aren't flexible). Challenge your thoughts, what would you rather be thinking? If that doesn't work, try acceptance. Say to yourself 'im having the thought that...' then 'i notice that I'm having the thought that...'. Thank you mind for giving me this thought but it is no longer resourceful.
I hope this helps :)
I hope this helps :)