Is Constant Discomfort In Lower Back A Serious Cause For Concern?
Does't look alarming but some rest and a x-ray are advised.
I read your question carefully and I understand your concern.
Judging from your description of pain as well as the lack of red flag symptoms such weakness of the lower limbs, impaired bladder or bowel control, persistent fever etc, there is no indication of that pain indicating a threatening condition. Most likely it is due to degenerative arthritic changes of the spine, changes which with age start to present. The fact that it is more pronounced when putting a weight on the floor makes intervertebral disc issue more likely as bending forward puts more weight on vertebral bodies, doing that carrying a weight even more naturally.
However since the issue has been present for two months a simple cheap exam like a X-ray, while not urgent, would be advisable. In the meantime perhaps you should consider at least for a while to avoid lifting weights, as the spine is one of the main weight bearing parts and you should live it some time of rest to allow for the inflammation to subside. Exercises to strengthen back muscles and strengthen your core would provide more support to the spine. If symptoms increase in time even after some weeks of rest, perhaps then a more detailed exam like MRI may be scheduled.
I remain at your disposal for other questions.