No one on here can tell you whether or not you should go to the ER. If you are seriously concerned then go get a check up. You may have some sort of health condition which requires medical attention, but I have never heard of anybody being hospitalized for caffeine addiction/withdraw. I've had psychotic episodes and seizures from opiate and benzo withdraw and was only hospitalized after seizure once. Another time I was in jail in a padded room. There isn't much they can do for even serious withdraws besides anti psychotics and hydration.
I can almost guarantee you will get better responses if you don't spam TDS with multiple threads and you elaborate upon your condition. Emergencies belong in the ER not in an online forum. All we can do is offer advice and support.