How does the medical treatment makes you feel?

Hello all, I was diagnosed with depression a little less than 6 weeks ago. I started taking Sertraline, but I was having lots of secondary effects like fainting and shaking in my hands. Although my mood was improving it was necessary to change the medication due to secondary effects. So a week ago I started taking Citalopram, I haven't had any issues with it. However I feel strange. It's like I know I'm sad, I know I'm not happy, but I can't cry or express my feelings. I feel like I'm forced to be in a good mood and keep going in automatic mode, but deep down the sadness is still there. It just can't be expressed... Has this happened to you? Does it get better?