Can i go to the er for a really painful wisdom tooth?

No: They are absolutely less than useless. You need to go to a dentist that does extractions. Then you can be properly treated.

You can..: ... But don't expect to have the tooth extracted. They don't do that in the er. You will wait 5 + hours and then be given a prescription and told to call a dentist. You've just saved a whole lot of time and frustration by posting on this forum.. Call a local dentist or oral surgeon and have the tooth extracted.

Yes, but...: ..it will be a wasted trip. Wisdomtooth extractions are not performed in ERs'. You will have to see a General Dentist, or preferably an Oral Surgeon, for treatment. So call your Dentist and ask him/her which Oral Surgeon to see in your area.