I'm 6 days off perks, how can I keep my anxiety under control?

Depends. Anxiety from opioid withdrawal is self-limited and will get improve over the next few weeks. However, there are many causes of anxiety, and the treatment may depend on the cause. Meditation, muscle relaxation techniques, creative visual imaging and other non-drug techniques help anxiety. Meds may help, but benzos (xanax, klonopin) also produce dependency. See a mental health specialist if persists.
Breathe. Exercise is a great way to relieve stress. Your body releases endorphins during exercise, which can help you feel calm. If you exercise 30 - 60 minutes a day, your stress levels can improve. When stressed, take 5 slow, deep breaths with your eyes closed, then roll your shoulders forward 5 times, then back 5 times. This will slow your heart rate and reduce tension in your shoulders.