Trazodone is an AD as opposed to a sleeping tablet (like zopiclone). I've never used it but there are ADs that help with sleep eg mirtazapine so I'm assuming this is why your GP has given you this instead of Prozac. However, like all ADs, it's probable it'll take several weeks to kick in, which may be why you're not feeling the benefits yet. You may need to just be patient for a little while, hard as it is