Dear Welcome to HCM We understand your concerns I went through your details. I suggest you not to worry much. You are suppose to refer to concentration and attention as two. Attention span for any adult is maximum 30 minutes. Sometimes, a person can be attentive to an interesting thing for more than 30 minutes, such as movies or games. Concentration is attention plus understanding. For this too, span os below 30 minutes. If you are able to make your studies interesting and based on variable principle, your concentration level can be increased. it is also possible to improve your concentration level with the help of yoga, meditation and breathing exercises. If you require more of my help in this aspect, Please post a direct question to me in this URL. http://goo.gl/aYW2pR. Make sure that you include every minute details possible. I shall prescribe the needed psychotherapy techniques. Hope this answers your query. Available for further clarifications. Good luck.