My best advice would be to try this book
https://www.amazon.com/Schaums-Solved-Problems-Physics-Outlines/dp/0071763465
(There's a free pdf somewhere in the internet just google it.)
You should write down your thought process as you try to solve the problems (If you can't solve the problem, try writing the solution in your own words [provided you understand the solution! Not understanding the solution evinces a lack of understanding of the concepts, in which case you are better advised to review thereof]). Lastly, don't fret, most of the intellectual nuances you depict are ostensive, meaning that they are perhaps not only practicing more, but better; there is no scientifical convention that can ascertain a disability to do physics, your cohort has a broader cognizance in the respective subject and therefore better mental representations (of physics), that's all. Practice!
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Also, be patient, we all learn at different paces, being slow or fast does not preclude one's ability to excel in a particular subject. Good luck!
>Physics questions that I haven’t tried before are so hard for me. If I’ve seen a similar question, it’s really easy.
That's the trick. Get practice tests/exams/questions with the solutions and practice, practice, practice.
One good recommendation is the "Schaum's Outline" series. These books (for a large range of science and math topics at different levels, have a very brief theoretical section followed by a TON of exercises, with solutions.
In your case I think "Schaum's Physics" is the appropriate text. This book will have short explanation of the material (for more details check your own textbook in case) and then like 3000 problems you can solve. Not all will be mechanics, but there are probably dozens or hundreds that will help you. (For college students there is also "Schaum's College Physics").
Just do this book.