Hello,
Thanks for posting your query.
This looks like a positional anomaly or a mechanical back pain. The low back ache is a result of muscle spasm which in itself is a protective mechanism body develops so that the back avoids abnormal posture. For pain to go, it takes not only rest (on a comfortable bed) but also avoidance of particular positions (during work, rest or recreation).
While on work don't sit in one position for more than an hour and take frequent stretch breaks. Do not bend forward to lift things up, bend the knees and hips for that. Also discontinue any strenuous activity or exercises for some time.

Having said that, you might want to consult your orthopaedician for a detailed physical examination and appropriate investigations. It might help with few medications like pain killers and muscle relaxants and physiotherapy for a few days. Physiotherapy particularly lumbar traction for a week and back strengthening exercises after pain relief work well. You can do a regular hot fomentation in the affected area and apply a local analgesic gel too. Being slightly overweight is not helping you too. Losing a few kilos will help in decreasing the wear and tear of weight bearing joints like spine, hips and knees.

Remember that medicines usually don't play a role in long term treatment, what does is exercises. Few exercises that the therapist will teach you must be done for life time.

I hope this answers your query.
In case you have additional questions or doubts, you can forward them to me, and I shall be glad to help you out.
Please accept my answer in case you do not have further queries.
Wishing you good health.
Regards.
Dr. Praveen Tayal.

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