Another couple of ideas - check the tension on your machine. Also, if you are moving your fabric faster than the machine is running, you risk breaking needles and saying bad words! :roll:
If your bobbin goes in a case, you may want to have a separate case for straight stitching, and a different one for when you adjust the tension for fmq. Put a dab of colored fingernail polish on one to differentiate the two.
Also, practice practice practice and give yourself permission to not be perfect right out of the gate.
Most importantly, enjoy the ride! Feel free to contact me if you want to chat.