Should I see a doctor about lower back pain that has persisted for a week?

Hi. You may see a GP or a chiropractor soon.

Watch your posture.

Be careful when lifting heavy stuff.

https://www.youtube.com/watch?v=L_xrDAtykMI&t=6s

Whenever you are questioning going to a doctor, just go to the doctor.

you need lots of minerals, and read the borax conspiracy, ionic minerals, and not just a dose or two or even a bottle or two. a doctor may prescribe some pain killers, but that is so very dangerous.....and maybe some gentle stretching may help, not vigorous, in the morning, and throughout the day, on break just toe touches and trunk twists just to keep limber....don't tell the doc you heard it was minerals, ...you don't wanna go there......egos involved and money......

Also agree with the Chiropractor option.

But are you sure you don't have a UTI which has gone up towards your kidneys? Temperature normal, no hot flushes, no confusion? Urine looking normal?

I would see a chiropractor. A regular physician can't do anything about the source of the pain, they can only give you medication to mask the pain, which does not sound like what you are after.

Chiropractors can be kooky with their "wellness" nonsense, but they can at least make adjustments that will un-kink whatever is causing you pain. I'd go sooner rather than later, as the longer you wait, the more your body will get used to being misaligned, making it more likely you will re-injure yourself later.