Dude... this is not rocket science. If you are having anxiety attacks because of something you are doing STOP DOING IT. I know it sucks but it is what it is. Guess what? I can't take strong pain killers. Perks, oxys, etc... they just make me puke instantly. So when I get a broken arm or something I'm stuck with stronger doses over OTC analgesics. It sucks! But I don't continue to take perks and expect a different result... understand what I'm saying?
I don't know nicotine to cause anxiety but it can make you sick, and depending on your blood sugar levels if you take enough you could absolutely get heart arrhythmia, sweating, etc... all symptoms that anxiety attacks produce. So you could be confusing nicotine poisoning with anxiety attacks. LOTS of cigar smokers get sick from nicotine because they're used to smoking normal, mild blends and then they get a big, heavy, full flavored bad boy (some triple and even quadruple typical nicotine content of analog cigs per puff) and they get sick. They puff too much. So what you could do it keep it to one or two puffs per minute. You could make sure you eat something well before you vape, and vape with a nice cola or other sugary beverage to help keep symptoms at bay. SUGAR... not artificial sweetener. Or simply bump down your nicotine levels in your juices but you don't seem to want to do that.
Of course, if you say it's anxiety and the ER says it's anxiety you are very possibly having a reaction to the nicotine juice. It could be something either in the flavoring, the delivery system, something somewhere is giving you a bad reaction. Lots of people are allergic to PG but I don't know if it produces anxiety symptoms. Its either nicotine poisoning (which would mean you could still vape you just have to alter your technique and prepare properly) or it's a bad reaction... either way I'd bet a doctor would advise you to stop vaping if it's making you this sick. You should go see your family doctor who knows you a bit better and tell him what you told us, he might run some bloodwork to see if you have an allergy or something.