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https://www.youtube.com/watch?v=HxvRQ9ZJ8vQ Chiropractic Mobilization will help. Avoid bending in front. Postural Correction- Sit Tall, Walk Tall. Extension Exercises x 15 times x twice daily. Apply Hot Fomentation twice daily.

It's commonly due to weak abdominal muscles. Video consult me online for detailed evaluation

Well you need lot of exercises along with manual therapy treatment.check out the video

You should consult a Physiotherapist in person or through online for complete assessment of your posture and cause for your back pain.

You need postural correction exercises, for better assessment and treatment consult in person with physiotherapist near you and start the treatment.

Increased lower back curve can be corrected with core muscle strengthening that is back and abdominal muscles With posture correction As you stated one side pain Check the symmetry of pelvis ( hip bone which is prominent) Correct it if asymmetrical Change ur chair and work postures Ice pack for pain relief

Do some spinal extension exercises like bridging exercise, cobra pose exercise,cat and camel exercise.