Thanks for your question.
The back pain is not due to the epidural injection.The pain due to epidural puncture will last for few days only.It will not last for 3-4 months.
This is likely to be related to degenerative changes in lumbar spine which are common with advancing age.Pain during night and at start of day are typical for lumbar spondylosis.
You need to have an x ray to confirm lumbar spondylosis which can be treated with physiotherapy and postural care.
You may need analgesics as per need.
This is my initial answer.Please reply if you need any clarification.
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