In 2018, when the market crashed, I saw my cryptocurrency holdings fall by almost 90% and I felt very bad at the time
But I learned some good lessons that can help you:
1 - if you're too worried and uncomfortable, you may be too exposed, maybe it's better to have fewer cryptos
2 - If you're confident in your position, don't get weak if the price doesn't follow what you planned
3 - Don't keep checking the price every day. Working on other projects helps a lot, especially studying more about the market or getting involved in another activity, thus making your time useful
And please, don't sell at a loss