Back Problems?

I've been having back problems these past few days and this has happened a few weeks earlier as well. I feel a pain in my lower back when I bend down. I got this problem when I was playing bball and I turned too fast. Before that I was doing alotta abdomen exercises and weights. I had this problem in the past a few times, once when I visited the doctor she said I'd pulled a muscle. Id prefer not to visit a doctor or a chiropractor in this case, how do I fix this problem and lesson the pain?