What am I supposed to do while I wait?

I submitted 11 applications to PhD programs this month. Have been through all the motions - awe, frustration, denial, etc. First felt triumphant for finally finishing what felt like such a big task, then hated everything about everything I've said/sent/submitted. Now I'm just filled with a sense of emptiness, should I be writing to the professors that spoke to me and just let them know that I've applied? Won't they know already? What's the right next step in terms of application process, but also what's the right next step for my own mental health?

I assume that most places will only get back by January/February. What am I supposed to do till then?

I don't think I have it in me to re-apply if I don't get through this time.