Hi! I believe I can be of help with this issue.
First, let me say I can imagine how frustrating and distressing this situation must be for you. Your problem, however, does not appear to be consistent with ADHD. That's good news. Because you are clearly bright and capable. So having a specific problem is easier than an overall cognitive problem like ADHD. What, then, might be going on here?
There are two problems that emerge as most likely based on what you have written. One is a form of dyslexia and the other an anxiety reaction. It is possible that your brain is not processing the information you need to concentrate on because of the background noise, that it can't "tune out" the background noise. The filtering mechanism may not be there. In that case you would have to get help from a specialist in this.
But I'm not convinced this is the leading contender here. Why?
Because you've gotten this far without having this problem. This form of dyslexia would, from my understanding, have been present throughout your school career. The late onset of this problem just doesn't conform. But keep it in the back of your mind if the next possibility is ruled out for some reason.
And that is an anxiety reaction. The timing of the problem's onset is very consistent with this. The fact that you are very bright and capable is not, you might be surprised to find out, a protection from these anxiety symptoms. Often, capable people, will have somatic (physical) symptoms that result from anxiety.
Now, you are a young man and aren't reporting any other problem. I therefore am going to recommend something unusual. I rarely recommend hypnosis. But here I'm going to! Why?
Because there is no other symptom of a life problem that is debilitating going on. Now here's the important statement about hypnosis: hypnosis can help with a specific problem and that's why I'm thinking of it. HOWEVER, there are good and honest hypnotists and there are other types. Your only way of assessing is two ways: first, make sure he or she is a licensed psychologist. Don't let anyone tell you they are a licensed hypnotherapist. There is no licensure in most states that I know of. It's all a "self-licensing" which is not good enough. So you want to know his or her license number as a psychologist and call the state licensing board to make sure there have been no complaints filed.
My hope here is that you will, like a smoker, be able to use the hypnosis to not have to have the anxiety reaction continue just as a smoker can cease his anxiety reaction of holding a cigarette to his lips, etc.
This is a relatively quick way to see if you can deal with the problem as a symptom. If, however, you are not a good candidate or it doesn't bring relief, then you should consider psychotherapy for the underlying anxiety. You would then talk with your therapist about the possibility of that form of dyslexia and investigate it as well. But I hope that this straightforward approach will help you; it's worth trying first.
I wish you the very best!
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