Stay in the moment Ms. Rrio. It sounds to me like your doctor was not agreeing to that plan. I also think that is an aggressive return to work plan. You said your doctor wants you to ease back in slowly. I am not sure he is agreeing with their plan. I think this plan can be changed as needed. I don't think it is written in stone. This is the plan they would like to have you accomplish but if you need to take it slower, I think they will be accommodating to you. You seem an important employee for your employer and I am sure they want you back but want you back ok and working good. Not pushing you too hard and causing more problems or loosing you.
You also still have the six weeks to go. That is almost two months. You reported in your signature that your speech (stuttering) is improving quite a bit and the prism glasses were helpful. This is progress. You still have the six weeks. Go through that first and then see how you feel. If you are not up to work by the end of the six weeks then you and your doctor and employer can come up with a kinder, gentler plan. Lets wait and see how your doing after those six weeks of therapy before you worry so much about returning to work. What's the worst that can happen? You won't be ready and will have to take more time or you might have to quit or get fired. No big deal. You are a smart lady. Things will work out. Don't let the anxiety over what has not happened yet and may never happen bother you now. Take it one day at a time.
Best of luck to you. I am pulling for you! This is going to work out ok!
Love,
Brain