I have always suffered somewhat with back pain and was diagnosed with Scheuermann's Disease as a child/ teen. I am now in my 40's and I don't know what to do. I suffer with lower back pain and hip pain on a regular basis, and yesterday and today I am unable to do anything. However I sit, stand or move I am in pain. In general if I stand for more than 30 mins my back starts playing up and if I walk around town ( on pavements) after 45 mins I am in need of some rest. Oddly enough, walking the dogs across fiends etc doesn't seem to make it flare up. Paracetamol and ibuprofen is not touching it. i gain a little relief from a very hot water bottle.
I am 5ft 5 and not overweight.
It sounds like maybe you need to see a physical therapist who can set you on the right path for rehabbing your movement patterns and posture. Then perhaps a personal trainer who specializes in corrective exercise to teach you which muscles to strengthen and which ones to loosen. Building strength in the core, legs, glutes, and muscles that support the spine can help correct improper posture. Also, have you tried using ice instead of heat? Ice reduces inflammation which can potentially relieve a lot of pain. Heat can induce inflammation and keep pain levels high. Good luck to you.
It's good that you're not overweight because I think in my case anyway it is making my pain at least a little bit worst. From everything you've described from walking on hard surfaces versus soft surfaces I think your problem is in your shoes. I have problems with my feet and my lower back but my podiatrist recommended New Balance tennis shoes and inserts in the shoes. If you have a New Balance store where you live I highly recommend you go in there. The staff is well educated on fitting shoes and figuring out what's best for you. Unfortunately it is considerably more expensive. I think I paid as much for my inserts at New Balance that I paid for a new pair of New Balance shoes from Famous Footwear.
Do some stretches like:
Lizard Pose
Bound Angle Pose
Pigeon Pose
Half Fish Pose
Garland Pose
If it is not helpful then please look for a physiotherapist.
Where do you live? I can suggest you some best physiotherapist in your location.