Day 3 of nofap, am I feeling withdrawal symptoms, or negative feelings I avoid facing with PMO?

I have read that anxiety, depression, and insomnia are side effects of porn withdrawal, but these last couple years I feel like I haven't accomplished anything. And over 15 years of regular porn use I have wasted a lot more time and probably missed out on many experiences. I know it's pointless and irrational to think about the past like that, but it's hard not to right now.

Everything I have to do to reach the point that I feel I should be in my life right now seems insurmountable. How long until these feelings pass? How long until I can sleep normally without PMO? Is what I'm feeling right now just a result of how badly I've messed up my brain chemistry with this stupid addiction, or will this pass in time? Do you have any advice on how to overcome these feelings, or easy ways to get to sleep without PMO? I feel like crap right now.