Thank you for the information.
Based on your description, you have lower backache which is radiating to your side/groin. Since it started after a heavy lifting, musculoskeletal and spine related causes are likely. It is good to know that test repost came back normal, that means no disk problem. There are many other potential causes of lower backache such as arthritis, kidney problem, sacroiliac joint dysfunction, pinched nerve, trauma, muscle pull etc. Good thing is that most people with arthritis, musculoskeletal or minor issues manage their symptoms with conservative measures such as rest, ice/heating pad, mild stretching exercise, physiotherapy
, and pain meds. OTC meds are generally good for these purpose, but stronger pain meds can be prescribed in a situation when regular pain meds are not helpful. In your case, you are already on stronger pain meds so just continue with it. Almost 80-90% patients benefit by there measures, however, in those who do not respond to these treatment other option can be considered depending upon the cause. It is also important to note that, lower backache can be also due to nerve compression/irritation, in that case also these conservative measures are helpful. For nerve related pain meds like lyrica, neurontin can be also considered for better pain control. Depending upon the cause, many treatment options are available, you can read more about it from this link:
Since you have history of sciatica, nerve related issue is possible, but it is also important to rule out other potential cause such as sacroiliac joint dysfunction which can present like this. i don't think that it is a kidney related problem because you don't have any urinary symptoms. You can visit an ortho doctor for proper evaluation and management.
Please let me know if you have any other question.