Sex drive?!

Can it take some time for Prozac to affect sex drive? I'd read other posts about dealing with this side effect but I didn't notice it at 10mg or when I was upped to 20mg. I've been on the 20mg for two months now and I (as well as my partners) are noticing a significant drop. I don't know if it's something else or the medicine. I have missed a couple days of taking it and noticed on those days I'm super aroused. But idk how that can be when this stuff has been in my system so long.

Also, I'm just noticing this isn't working as well for me as it used to. I've had some of the worst days ever while on this than I ever did unmedicated. However, I still have more better days. What do I do?