I'm having lower back pain, mild cramping, headaches, naseua, sore throat, and i'm extremely tired. what could all this mean?

You need a doctor: These symptoms strongly suggest a need for a visit to a good diagnostician. Put together a written list of each and every symptom, the things with which they are associated, the times they occur, your temperatures and pulse and respirations when they occur and take these with you and expect a thorough and detailed exam and some testing which may include imaging studies. Good luck.