What Causes Muscle Spasms In Lower Back Along With Abdominal Distention?

I had what I though were muscle spasms in my low back a week ago, and i almost took my breath away to move a certain way. I teach yoga, so I thought it would improve after a gentle class, and I had done about 4 hours of driving the day before, so I thought that was it. It didn t improve, and for a week I ve had abdominal distention, gas, but normal stools, but still some kind of muscle or intestinal pain in the low back on either side of my spine. For three days I had a bad headache behind one eye, but that is gone-so I thought I had some kind of virus. I can t tell whether it s muscle or something else. It has moved a bit to more of my lower left back and it s been interfering with my activities. I m also full very quickly after I eat and don t feel the best.