Re: 22 year old, is everything okay?
Is is possible that it is colon cancer, but not very likely. If you have no history in your family of early onset colon cancer, the chances of you having it at your age are quite remote.
Your doctor is correct that the most likely answer is hemorrhoids. That having been said, I am a firm believer of trusting your instincts. If your gut is truly telling you that something is amiss, follow up with it if you can. Otherwise track what you are eating for a while as it could be simply something you ate that you were hypersensitive to.