Hi Lara, I took these years ago. I think I felt a bit better within a week tbh, even though doc said it would take longer.
It was gradual, but about six weeks after I started taking them, I was out one day and I realised "I am not completely miserable, I may even feel.... content-ish". It was a good feeling!
Keep taking them. THe only side effect I had was that I kept losing weight. I am only small, but I went down to about 7 and a half stone and they did make me get diarrhoea, but not awful, awful diarrhoea, it was livable with you know?
But everybody thought it was that I had no appetite. My appetite had returned while I was on them actually.