How soon is too soon?

I unfortunately had to lay my first cat to rest yesterday... He was only 2.5 years old but got diagnosed with lymphoma and basically spread to his entire body within a matter of days. I’m an introverted single guy in my late 20’s and my cat was absolutely everything to me (my entire life), I’m devastated but know he is no longer suffering.. anyways my question is how long should I wait before adopting another cat? Cheers Rest in paradise Gordon❤️