Get thee to a Physio! And... Keep moving!
I get lower back pain, related to a disc problem, if I sit around for too long, or stay in bed - even if I am Ill, it starts giving me trouble.
Last year I stood at a fireworks party for a long time and the next day my back hurt, within two days, I had pain down my legs and couldn't walk, I had slipped my disc, the physio. got me walking and gave me exercises to do, to help my core muscles - which support the back.
Drs., are not always the best for backs and waiting to see someone can take time, a Physio. will let you know what is going on with your back and hopefully sort it.
I was within a breath of having a major operation.
Sitting down is one of the worse things you can do. Take loads of painkillers and keep mobile!
Best of luck.