I can tell because I'm not sad anymore, I don't cry at the drop of a hat or have a constant lump in my throat. I just don't feel so low and desperate. The way I feel now is pleasant; it's a feeling of contentment. I feel more enthusiastic about life and look forward to the future. I can actually enjoy activities - - for example I had a blast just bowling and listening to music the other weekend. I enjoy myself around people more. Just generally feel better; it's hard to explain.