At the age of 25 yrs , complaints of diplopia ( seeing two objects in stead of one) is rare but usually two reasons, first more common lat  rectus palsy of either eye or convergence insufficiency, history important because it occurs all of Sudden , first you should consult experienced ophthmologist to find out ocular causes & if there is no ocular cause, then you should consult Neurologist with DM qualification in Neurology.