Hey there, Many people are experiencing what you're feeling right now and therefore, I just want to reassure you in saying that you're not alone. This is definitely something that could be resolved with a little bit of hard work! You are *not* completely useless! Many people have trouble readjusting to school after the summer break. It's nothing to get down about.
Honestly, I had the same problem that you're having right now in the past. Everyone experiences times like this but it's not something that is permanent. Like I mentioned, if you really work hard at it, you can create good study habits and develop time-management skills that could really help a lot.
I am not English but I do know how the educational system works over there. Your A-levels are very big exams that are crucial for your future. I could only imagine the stress that you're feeling right now. I'm sorry that you feel this way but I have a link that is geared towards dealing with stress that you may find very helpful.
Stress Information
Like I mentioned before, many people have experienced this same type of situation. Don't let it get you down! You seem like a very intelligent individual and therefore, I have no doubt in my mind that you can overcome this and be the successful person that we both know you can become. I have a couple of links here that may also help you a lot.
Study Tips
Tips for Concentration
I really hope I've helped. If you ever need anything at all or feel the need to discuss this further, don't hesitate to message me any time as my inbox is always open. I am always happy to help.
Good luck and I hope everything works out for you.
DYL
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You're like a bullet to my brain, I'm numb, can't kill my fun.
If you're good and done then thank you just the same.
I don't owe you anything.