Normally these types of drugs take 2-4 weeks to get into the system. Maybe you are just reading about the drug and worrying about what may happen. Please remember when you read up on drugs and the side effects they list may have only happened to 1 person in 100,000 people but they have to list it.
Please give it a chance. Normally your doc will then want you to try it for 3-4 months once it is in your system. However, if you are not comfortable with it, don't let your doc talk you into it. It may be that you need a different drug.
Take one day at a time and see how it goes. Keep posting and other people will share with you also.