Having weekly anxiety attacks, im out of my anxiety medication and can't afford to go to the doctor right now, can I go to ER to get my refill?

NO. Most emerrgency rooms will not refill controled substances. In the long run their bill cost you more than an office visit.
There are ways. The two main forms of treatment for anxiety and panic disorder are medications and cognitive behavioral therapy (cbt). Cbt is very effective. It involves: exposure and response prevention therapy whereby a person makes themselves have a panic attack on purpose and then does nothing to make it go away, allowing it to go away on it's own. Then the body desensitizes itself and the panic stops.