Hello and welcome! Can you give us a little background about your anxiety? When did it start, what are your symptoms?
To be honest, even if there isn't a contraindication between the Cymbalta and marijuana, I would advise steering clear of it completely, at least until you get your anxiety under control. Reason being is that MJ very commonly causes anxiety, or exacerbates it, and very possibly, it may interfere with the effectiveness of the Cymbalta.
Is this is the first medication you have tried for anxiety? Are you in any kind of therapy?
Hope to hear back from you so we can understand a bit more what brought you here. Take care!
I have limited experience with both drugs and never used them together, so I have no idea, but if pot is legal in your state you should ask your doctor. If not, I'd search the web for interactions between the two. If someone on here has experience with both hopefully they can be of more help than I am. Good luck!