Brief Answer:
Wrong postures and wrong sleeping positions should be corrected.

Detailed Answer:
Hi

Thank you for asking HCM

I have gone through your query. Pain related to spine can be most likely from wrong postures while sleeping as well as sitting.
You should use hard and firm mattress for sleeping. Using orthopaedic pillow for neck is also helpful. Avoid high pillows. Use one or to pillows to keep between knees while sleeping. Avoid sleeping on stomach.
While sitting also using doughnut neck pillow is better. Avoid sitting for long time as it can increase load on spine. Lifting heavy weights and continuously leaning forward should be avoided.
Giving hot fomentations on upper and lower back with help of some one is good. For Back muscle strengthening exercise you can refer this video https://www.youtube.com/watch?v=ccFHpn-_Dfk. If more pain is there then don't go straight to exercise. Do hot fomentations daily , rest for 5 days and if it improved then you can start exercise.

If there is no improvement then consult an orthopaedician and do x ray/ MRI of spine to rule out intervertebral disc herniations or arthritis. In that case you may need to go for physiotherapy.

Let me know if anything not clear.
I am happy to help you.
Thanks.

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