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I think that it would be worth it for you to try another doctor. I know that yours has done blood tests, but if she doesn't want to look beyond the blood tests to look for other causes of what may be going on, it could be worth it to get a second opinion from someone else. A second opinion would allow you to either hear that there's no other tests that can be done (but I'm sure there's something), and they may even show more concern over what's going on, recognize there is a problem, and run more tests.

I think that if you have insurance, you can call the insurance company and they can give you a list of doctors that are covered by your insurance. Then, you can call and make an appointment. If not, you can always talk to your current doctor and ask for recommendations, do an online search, or even ask the people in your life if they've seen a good doctor.

Then, you can sit down and talk to your mother and let her know why you are so concerned about seeing another doctor. Let her know that your health is very important to you and you don't feel as if your current doctor is doing enough for you. Tell her you know it's hard, but you really want to get better and think seeing another doctor is the way to go. Honesty is key!

Best of luck! I hope all gets resolved!