What Causes Pain In Mid Back On Right Side?

Could this be serious? I ve had extremely bad mid back pain constantly for 2 months on the right side. I feel inflammation around spine area & I ve been dizzy & lightheaded. I ve had this pain on & off for about 10 years when I went to Argentina I got really sick & had this bad mid pain with infection. They said I had a kidney infection & had blood poisoning. It s been going on for years but getting worse it comes & go but this has been 2 months now.