Hi thanls for your question.
Your having intervertebral disc
herniation at L5 -S1 level with posterocentral annular tear causing mild impingment on thecal sac
and bilateral adajacent nerve root
.Most probably this condition could be due to mild trauma or improper postions while doing differnt jobs involving your back.Since herniation of disc is associated with annular tear and impingment on thecal sac and nerves on both side,this condition needs medical attentation,if left untreated can lead to further damage and even can cause paralysys of lower limbs
.I would suggest you to consult an orthopediac surgeon or a neurosurgeon who may be able to tell you,this condition needs surgery or not.Mean while I Would suggest you to take proper bed rest
,avoid all sort of jerks to your back and adopt proper position while doing minor jobs involving your back.
Hope this answers your question.