Need Help! Only 20

I'm only 20 years old, I used to run everyday until an injury a couple months ago, so i'd say i'm a healthy person. 2 years ago there would be blood on the toilet paper when i'd make a bowel movement, and I thought it was just hemorroids. Then about 6 months later I went away to college, my diet was all out of wack because I ate cafeteria food. But I started noticing problems. I felt like I had to make a bowel movement all the time, even after I had already made one. I would make maybe go 5 times a day and still feel like I had to go. I noticed there was a lot of mucus in my stool, and some movements would be just mucus. There was blood here and there. I thought maybe it was the food. So when I came home this summer a lot of the symptoms disappeared. Until the last couple months they have all come back, and i'm eating healthy. But the last couple weeks there would be times I would lose my appetite, and the urges to go to the bathroom have gotten worse. There seems to be a little more blood, and I get a lot of stomach aches, but they are weird ones. I know I should see a doctor, which I am going to do. But I am kind of scared, and all along i've been convincing myself it was food or something else.
Thank you