I forgot to remove my tampon on the last day of my period in October of last year. I hadn't realized anything until a few days later, I had sex and there was a brown, watery discharge. I started noticing brown discharge all of the time. My back and thighs were also sore, almost like having a pulled muscle. Thinking it would go away, I left it alone for a while. I was still having a normal period, besides the smell. A couple of days ago I read it could be a lost tampon, it was. I removed the tampon and all of the symptoms are gone besides the pain in my leg and back. Could this be some kind of infection from tampon that has spread through my body?