Crash & Burn (Suggestions Please)

This morning I had every intention of getting up and doing some quilting to FINALLY get this one project finished.  I got my machine ready and prepped myself mentally. 

I started free motion quilting.  After a few swirls I stopped and checked out the back.  The thread was pulling in the curves of the the loops.  I loosened the tension and same thing happened. 

Needless to say I stopped and I am now in the process of ripping out all of the stitches. 

What should I have done differently?  Was it possibly because I was getting close to the end of the bobbin?  My tension was off?  I’m ready to try more free motion, but want to try and avoid this in the future.