Determine the valence intensity of the following tweet, considering the mental state of the author. Assign a real number between 0 and 1, where 0 denotes extremely negative and 1 denotes extremely positive.
Tweet: @ExpressScripts u shd b embrrssd. u jack up my bp meds twice and it will still take 3-5 days? Not express at all. #expressscripts #horrible
0.172