Since we cannot physically see the inside of your computer...we can't answer that question.
Based on the information you've provided us...yes, that could be one of the problems. The trick, here, is to rule out one probable cause...and move on to the next.
If you're not comfortable working on the inside of a computer...then you can have someone perform this for you. Once it's done...and you're still experiencing the same issue, we can move on to the next probable cause.
It appears you're not comfortable doing this due to...and I quote you...your "clumsiness"...then I highly recommend you have someone who knows a little more about computers do it for you...or take it to a PC repair shop...and have them diagnose it for you....giving you an estimate as to what it would cost to repair...
Best of luck...