Ok here I go. I do this every 4-5 months because there are always new people who come down with the exact same symptoms. You are not alone. This is my cycle:
1. Three weeks of all out WOD. Try to set PR's, push as hard as you can.
2. Every 4th week, take a half volume week. Cut the volume in half any way it makes sense: For today's workout you would run 5k. For timed workouts cut the time in half. For weighted workouts either cut the weight or the reps in half.
3. Every 12th week take a week off of organized training. Work gymnastics, rock climb, play with a new sport, etc. This would be a good week to loosen up your nutrition.
This thing ain't a race. I plan to be training until I die...plan some rest, you'll come back stronger and this gives you somthing to look forward to.