Effexor Sore Throat Pain, Venlafaxine, Pain in the Left Side, Pain in Left Side, Job Interviews

Having been on Venlafaxine for 2 years and feeling well, I am trying to "get off" them, have reduced from 37.5mg twice a day to a quarter of a tablet ever second day over 3 months and I thought it would be fine to stop now, one week on, I feel terrible, started with a terrible pain in the left side of my head and very bad pain in left side of neck, couldn't stand bright lights, during the week I have had weak arms, sore throat, pain in chest like being kicked, dreadfull dizziness, can't think properly, feel close to tears for no reason, head feels like i'm inside a box, sort of muffled. Dry mouth, waking very early in the mornings- about 5am. bad diaroea for two days, feel like I have jet lagg, now today on day 8, feel low mood and am terrified of depression coming back, think I will take a quarter of a tablet tonight as have a holiday coming up and job interviews, can't deal with this now, so may have to go back on them for while ? I was fine taking them, and felt completly well again although I have put on about 40lbs, am also on Lithium so could be that ? anyone out there having same problems with this drug, all advice appreciated.