I have been taking Prozac mg to lower my Effexor XR from 112.5 mg to zero. In about 10 days, I am now taking half of the 75 mg pill which is not 37.5 mg yet... bead counting. I am starting to get some effects: headaches, digestive issue, libido and added anxiety (hate this). Should I increase Prozac before going down to 37.5 mg... either 15 mg or 20?