Great thread here; Tunnelvisionary thanks for posting those insights!
I just wanted to chime in here and say to the OP that, at 21 years old, you are an adult, and thereby eligible to seek out the kind of care YOU WANT AND NEED, not the kind your parents think is best. You struggle with perfectionistic thinking—I do, too—and I'd bet that your parents have, for a very long time, been the ones primarily making the decisions in your life. I could be wrong, and I only say that because my parents were the same way, and that kind of upbringing leads to a more anxious personality, too, because we're never taught self-sufficiency. All of these character traits go hand-in-hand, naturally.
As a perfectionist, I can see how you'd like to simply accept your anxiety, stop your reassurance-seeking, and move on with your life. As someone who struggled mightily in the past with her own anxiety issues, I can tell you that getting over HA or anxiety or whatever you want to call it, takes A LONG TIME. It is, by nature, an imperfect process. If anything, going through this now will set you up for a healthier future, one where you're not constantly putting so much pressure on yourself to be "correct" all the time.
Don't expect yourself to just be able to accept your anxiety and halt any and all negative reinforcement behaviors in one day—again, that is UNREALISTIC, PERFECTIONISTIC thinking that you're going to need to let go of if you have any hope of moving forward in this process. You're going to fail. You're going to know, rationally, in your mind, that anxiety is the root cause of your issues, but you're still going to find yourself obsessively googling for hours—you're going to know it's not helpful, but you're going to do it anyway. You're going to have periods where you feel good, and then you're going to feel XYZ symptom and get fearful again and that's going to make you mad at yourself because you couldn't keep it together. The road to recovery here is really a two steps forward, one step back process. Acceptance happens everyday. You have to accept your anxiety every day—it's not just a one and done proposition.
CBT, psychodynamic therapy, these are both good options, but again, they take TIME. Months, in fact. Yeah, maybe your first therapist was a dog, but even when you find a good one, don't expect magic right away. The point of them is to venture into the underlying factors as to WHY you have developed an anxious mindset and to then learn how to reverse it. But just as you didn't develop an anxious personality overnight, neither will you reverse it overnight, either. So many HA sufferers (on this board and elsewhere) are merely desperate for symptom mitigation—they want to make the headaches go away, or the palpitations, and more than that they want to jettison that awful, oppressive fear. But, as we all have learned the hard way, none of that goes away with a medical test, a prescription, or a gentle word of reassurance. It goes away once we have managed to get our stress hormones down to pre-reactive levels, and again, that takes TIME and a gradual, habitual acceptance that what we're dealing with is anxiety.
I wish it were not that way. I wish we could all go visit a doctor once, be told we have anxiety, and never struggle with it again. I wish change was instant. But it's not. Again, you're young cameronj, and you have a whole life to live that doesn't include an anxious mindset. This process is going to be slower than you'd like; you're going to struggle; it's going to be sh*tty. But at the risk of sounding cheesy, there are better times at the other end. So do what's in YOUR best interest (not in your parents' best interest), be patient, and go easy on yourself. You'll get there eventually.