So something I tell my patients after they have had a surgery is that our goal with pain killers is to make the pain bearable rather than gone. Paracetamol is a great painkiller and helps opioids to work better. It's also non addictive and provided you don't take more than the packet recommends very safe.
For chronic pain the current thinking is it's multifactorial, but basically your brain gets set with your pain threshold too low, there is also a huge psychological element to pain and therapy or things like CBT can be hugely beneficial.
For me paracetamol and codeine have been enough to manage all the pain I've had, the worst being when I fell off my bike and smashed my ribs (pretty sure I didn't break any), luckily I'm in the 90% of people who can metabolise codeine to something more useful. Didn't make the pain go away but meant I could breathe a full breath without flinching. Codeine at lower doses just makes me a bit drowsy and slow. Good for getting to sleep.