I continued to eat ice cream but no soda or candy and my HbA1C was 5.6 and glucose was 83! I'm thinking about going high fat low carb! Should I?

Don't focus on this. You've got anxiety and a history of obsessive-compulsive stuff. You give no history of diabetes. Like most young adults and all physically healthy people, you can eat what you want without your blood sugar going out of control. Devoting emotional energy to food choices will rob you of the important stuff -- building relationships and achieving high-level physical fitness. That's REAL health.