Hi Beth,
That's an ok number for a +6, this is probably her nadir and she should hang around these numbers for a few more hours and then start to rise. Maybe feed her a little low carb food, you don't really want her to go much lower.
I would test again in 30 minutes. As long as you're home I would keep testing to see how much duration (when the insulin starts to wear off) she is getting, good information to have.