Is it possible that I have developed something concerning?

[CCrystal1212]

Hey, I'm 15, and have been pondering the cause of my symptoms.
My parents won't listen to me and think I have a hemorrhoid or experience these problems because of bad nutritional intake. Is it possible that I'm not mistaken for something much more concerning?

I've noticed the following:

Small blotches of blood in my stool (red blood on the stool, not in the water).

Mucus in my stool and on toilet paper.

Constant hunger, belching, relief of gas.

Trouble focusing; I forget about things all the time. I do not recall having this problem in the past.

Minor/mild-ish abdominal pain - I sometimes experience pain or grumbling of the lower abdomen when inhaling deeply. I do not smoke, but have a father that does. Outside, however.

Small, pellet-like, hard stool that's persisted for several months. It's not always present, but happens more often than not.

I've had a few narrow stools as well. Not pencil-thin stools, albeit ones that narrowed near the end.

Haven't had as many bowel movements lately. Eating a lot of food, and ingesting plenty of fluids. I'd say.. still 5 bowel movements a week? That's normal.

Have not suffered from nausea, diarrhea, or other common symptoms. It's not common for my age, and none of my ancestors are reported to have contracted this disease. I am a Caucasian male.