@Misfit Toy and @PatJ - I don't know if I have a herniated disc, though I doubt it - I have been symptom-free for probably 7 years or so and my pain stays localized in my lower back, it doesn't go down into my legs, buttocks, etc. I looked up the symptoms of a herniated disc and they seem most often to have the pain radiate down. I haven't seen my chiropractor or anyone else for my back yet, though I think I will see my chiro and see what he says about the cause. And like you MT, I just bent over to plug in a lamp and I reached at the same time, and boom! I was down, very very painful. My sister asked me if I had reached at the same time I bent over, which I did - and apparently it's the reaching at the same time as bending that causes the problem. Would have to do an experiment (which I'm not going to do!) to see if this is the case. Re the magnesium oil - it's in a salt solution and that is what causes the stinging. This salt solution causes the skin to dry out. However, I found it only stings if I have a cut in my skin - getting salt in a wound - or if my skin has gotten dried out from the "oil" (it's not really an oil). I think this stinging can be avoided if you (1) wash off the salt residue 20 minutes or so after application; and/or (2) apply some type of oil or lotion after applying the mag oil. Both of these will help. I've been using this https://www.iherb.com/pr/Now-Foods-Glucosamine-MSM-Arnica-Liposome-Lotion-8-fl-oz-237-ml/645 - it feels very nice applied on top of the mag oil. Re Hip's Epsom salt solution - I did try that when this first happened a few days before Christmas. I made a very concentrated solution and then applied it. It left a huge salt residue on my back and didn't do much for the pain, and even stung a little because my skin had a few tiny cuts because it was dry due to low humidity. As I said in the other thread, some 7 years ago or so my back went out like this and I was flat on my back for at least 10 days and possibly closer to 2 weeks before I was able to move around somewhat comfortably. This time it took 3 days. But I had to use ice several times a day, lots of Advil (not just for pain but reduces inflammation which helps healing, which I'm sure you know, and lots of magnesium oil, as well as gentle stretching for my lower back. I did all of that 7 years ago except not the mag oil - so I'm positive it's what enabled me to get better much more quickly.