HI COURTNEY,
When it comes to colon cancer it does not matter if you are 20 or 90 yrs old colon cancer is no respector of age, also does not matter if your family does now have history either, as my wifes did not have family history and she got colon cancer.
Ask your Dr to give you a colonoscopy, that will determine if you have colon cancer, dont give up keep pressing them as you are the one that knows your own body, Once you get a test and if every thing is clear, you will have peaceof mind .
God Bless You .. and keep going ..
Let us know how you get on ... Best Wishes ..