Writing a resignation letter, even if you're not planning to hand it in immediately, might help you clear your head and make a better decision. Handing in your notice straigh after another fire/argument/nuissance, i.e. in a direct response to a single event, might turn out to be worse than doing it when things slow down a bit—purely because you'll have more control over the situation and will be able to approach it with less emotions.
> anytime I see it’s too much
Honestly, why wait?