welcome to the bad back club.
please regularly de-stress and perform gentle movement exercise, such as circular motions and stretches regularly.
Remember that just because you can "manage" to lift something now, doesn't mean your back won't tell you about it several days later.
also, this sounds mad, but getting hammered drunk (and not doing anything strenuous while drunk) can alleviate back pain.
Since being fluthered, relaxes muscles so much, stops you thinking straight (holding onto stress) you're back literally cannot tense up, even if you use it as your personal emotional voodoo doll.
Sightly more scientifically, because drunk people are shit at balancing you're also throwing your centre of gravity around, and not holding it in one spot.
As well as this being what makes a drunken master style kung fu artist nearly impossible to knock over, and just as difficult to actually injure by striking,
the sort of "sloshing" around of your body weight makes it impossible for your body to hold stress at the spots it has grow accustomed too (i.e. in particular areas of your back). It's like an accidental, half arsed, message via one of those inflatable Gym ball things for what? 3~4 waking hours? and then a nights sleep with a muscle relaxant?
That's just the sort of break a stressed back needs.
so be good to your back; become an alcoholic.