I've no idea. I get the odd twinge and sprain (who doesn't at my age), but it's never really come to anything before. But it just sort of pinged two weeks ago and then for a day or two was quite incapacitating, but it didn't feel more than a bad sprain in the lower back really - so when it started getting better after a few days, I thought no more of it. The discomfort never really went away, but it didn't stop me doing anything.
Then I noticed when I was watching the parade at Brighton Pride last week that all that time pretty much standing still seemed to weaken it - not to the extent it was, I just felt very aware of it feeling weak, if that makes sense.
Then on Tuesday afternoon it went horribly again while I was carrying some shopping. And this time with burning pain in my left buttock. I've made a GP appointment, but that isn't for nearly two weeks.
It is definitely better today, but still feels sore and very sensitive and I wouldn't trust myself lifting or pushing anything. Thankfully walking around is okay, at least.
I think having even a lower level of pain for a long time is just grinding me down. I've never experienced it before.