I have been on Effexor for close to a year. I have vivid dreams, but I also take seroquel at night to sleep and that can make you have vivid dreams to.
It is a drug that tend to make people more active, so it should be taken in the AM so you sleep better. I had depression that made studying impossible. I couldn't focus, I would read three sentences and couldn't remember what I had read. This helped.
I would talk to you doctor about checking your thyroid because Effexor can give you hypothyroid disease and since the symptoms seem small it can go undetected.
DO NOT just stop taking it or forget to get your refills. It makes you sick, nauseous, and your balance is totally off. My sight was not goo either when I didn't realize I need refills and was off for two days.
I also had a decreased libido, but it got better after awhile. I am on a low dose, but overall I like it. Just PM me or reply here if you have any questions.
Hope that helped!!