I'm starting my fourth week on Topamax. I'm not sure if I really ...

I'm starting my fourth week on Topamax. I'm not sure if I really need to be on it though. My doctor sent me to a neuro for an EMG because I have bulging discs in my spine. Well, the neuro seems to think I have migraines and put me on Topamax and he added "this'll really make you lose weight". Well, I don't think I've ever had a migraine...just sinus headaches. I'm supposed to start 100mg tonight but I'm afraid to keep taking it. I keep getting double vision and tingling in my feet alot. I don't feel like myself and I'm not sure if there have been studies of the effects of this drug long term??