The weird side effects should go away in another two or three days or so. I'd say give it a week to two weeks total for it to start taking a good hold in your system. I had the same dizzy, out of it feeling the first couple of days. I felt sorta sleepy after I'd take it, then I'd feel like I'd chugged a pot of coffee for a while. I couldn't sleep the first two nights. But it went away very quickly! Stick through it and I'm sure you'll find it's worth it.
By the way, no sexual side effects with me from Effexor