Possible Back Sprain. It ll go away?

So, I had a huge basketball tournament this weekend, and I ve played in at least one game in the last five days (on some days three) and on Sunday (the third of five) I had a sudden pain in the middle of running in my lower back on the left side. So, it was really bad yesterday (day five of five) so I sat out for most of my games, and it s even worse today. During a practice today, I would find myself randomly and uncontrollably falling to one knee and being in a lot of pain. I also had a lot of trouble running and even just walking in general. But once I stopped moving it was fine, but worse than it had been before the practice started. I looked up the symptoms for a back sprain and they match perfectly. Do you think that s it or that it ll go away? I had a similar thing happen five or six months ago to a lesser extent that went away very quickly.