Hi, for a while now I've been dealing with really bad anxiety issues. I have anxiety attacks about once a week, but I have never been diagnosed with anything. I want to talk to my mom about seeing a psychiatrist to see if there's anything wrong with me, but whenever my sister talks about mental disorders, she always acts like its not a real thing. She'll say things like "If someone is anorexic they just need to eat more". Or, "if someone in high school is bipolar or depressed they just need to learn how to handle life" I want to talk to her about my anxiety but I don't want her to react in a way that will make me feel stupid. My anxiety also interferes with my school work a lot of the time. What should I do?

It´s the way you´re talking about your issues that will affect your mother´s reaction.
Try to be serious and don´t try to weaken your arguments because of embarrassment.
Your sister is not talking about her own problems, therefore your mum isn´t taking it seriously. She could see everything in a different way if she knew that this time it is you who is afflicted.