I have suffered from what I believe to be a lumbar disc issue and alleviated the problem with targeted exercises of the core. There is damage in your back somewhere, and the muscles go haywire and lock up, overcompensating to protect the damaged area.

No, physical core/back therapy is not "fun" work. It's not a quick, sexy fix, but the pain won't go away until the muscles are strengthened and "confident" in their abilites. Get a doctor's referral for physical therapy.

In the meantime, stick to ice, ideally in the evening when you're not gonna move around afterwards. DON'T MASSAGE the area until it's well healed. I've made that mistake, brutal.

I can golf again now pain free, despite my tendency to swing too hard, and I hope to be able to do so for 40 more years or so. I'm not a yoga guy, but it's great for the core and I might have to resort to it eventually.

Good luck