I have been taking 20mg fluoxetine for 1 month now. Prescribed for severe depression, stress and anxiety, as if by magic, I felt so much better after 3 weeks and was glad I decided to take them as I hate taking so much as a paracetemol for a headache. I am now 4 days in to my second month of tablets and these are a different brand - I noticed even the box felt different and the tablets slightly different as well. I was feeling really well and now have started feeling panicky and crying again and feel totally different. Is it possible there are no effective ingredients in this brand of fluoxetine?