I did Prozac for about two months earlier this year, a relatively light baby dose.
It was utterly terrible. I couldn’t think about anything, basically zero focus on anything that took more than a minute of attention span, I felt completely detached from anything resembling an emotion, and I also seemed to completely lose my ability to feel hungry or thirsty, so there would be entire days where I would forget to eat or drink anything, probably making all the other symptoms worse.
They transitioned me to Pristiq, which has been considerably less horrible, though not terribly effective either. I am actually undergoing TMS now.
If you're not responding well to SSRI/SNRI drugs, you could give bupropion (Welbutrin) a try. Just ask for a small dose at first. You may even be able to take them together with Pristiq. It's worth a discussion with your care provider.