Hello. U have not given much details about ur back pain. But mostly if it's not very severe like disc prolapse, then it ll b a normal muscle catch or strain. Best home remedy is apply hot fomentation and diclofenac sodium gel like volini or volitra . If required u can take pain killers n muscle relaxant like hifenac n movon MR or nucoxia and myoril . Hope you got the answer
Next Steps
if it doesn't come down after a week, go to a physiotherapist n get the treatment done