Is There A Thing as "Over Studying"

I'm currently in Med-Surg (second Semester of ADN Program). I study my butt off, however on the exam, I think I somewhat overthink the questions. Fundamental was a breeze. Well, kinda a breeze, I came out with an 86-B overall, but I'm really struggling this semester. Id do all the readings, make study guides based on the outlines. I'm almost about to give up. This would be a second degree for me and of course when things aren't going the way you feel you should, it's easy to think about other things that u could be doing. I don't want to give up, however, I only have 2 more exams and the final to get it together. I don't want to go into the final having to in the 80's.........too much pressure.

Our next exam is April 1st. It'll cover, oncology, ENT, Integumentary, Musculoskeletal, and Dosage Cal. that we get on all exams. Thank God, I'm good at the dosage cal cause that's sure points. I just don't know what to do about the other stuff. I study my butt off and I'm usually the go-to person in class. Lately. everyone that comes to me, score 15-20 points higher than me on exams and come to me saying "Thanks" when it's all over. Though I really like helping others and I'm proud of their success, I really need to figure how to benefit from my hard work. I'm struggling, and about to say *^#@ it all. Any encouraging words and advise would really help at this point.

Oh, Yea, I took an entire semester of test taking skills prior to starting the program. For some reason, I think I read into the questions. From fme reading into the questions, i sometimes change my answers........I only changed on the past exam, but heck, I changed it from right to wrong....what do I to do?