Dear
Welcome to HCM
We understand your concerns
I went through your details. I suggest you not to worry much. Attention depends on circumstances. You may be able to watch an interesting movie for 2 hours without any problem. But cannot concentrate on education related books even for more than 10 minutes. That problem is not lack of concentration, but lack of interest.
Regarding your forgetfulness - If you are able to remember (after a little while recollection) the food you had for breakfast yesterday, the story of a movie you last saw, the names of your friends etc, you may not have memory problem. If you are not able to recall what you read, then it could again be lack of interest during reading or listening.
Getting angry, frustration, rage etc could be fallout of this disappointment. Think over. If it is necessary, do consult a psychological counselor.
If you require more of my help in this aspect, Please post a direct question to me in this website. Make sure that you include every minute details possible. I shall prescribe some
psychotherapy techniques which should help you cure your condition further.
Hope this answers your query. Available for further clarifications.
Good luck.