New to kratom, seeking advice

I’m at my wits end with chronic joint and muscle pain. Doctors don’t know what’s wrong, aside from “fibromyalgia” which doesn’t offer much clarity in terms of cause or treatment. I currently take 800mg of ibuprofen twice daily, which is barely helping. I work full time in a chilly warehouse environment, which is making my pain so much worse. I’m worried if I can’t get my pain more manageable I’m going to loose my job. I’m hoping that kratom can help me, but I’m spread so thin between work and managing the pain that I barely have the capacity to do much research. What type of kratom, dosage, schedule should I start with to evaluate? I’m located in SoCal and can source locally at a shop or order online. Is there a preference in terms of quality and safety? Obviously the sooner I can try it the better, so I’d rather not wait for shipping, but I can wait if it’s really a better option than a local shop. Thanks in advance.