Weird gastritis symptoms?

I've been suffering from gastritis for 2 months now. I'm someone who drinks alcohol frequently, drinks coffee fairly regularly, takes NSAIDs often when I feel discomfort, usually eats heavy meals, smokes hookah, and I deduce that I've eaten foods I'm intolerant to (one of them is eggs), and I suppose my stomach got tired of me. First, they diagnosed me with colitis, I took a break, felt better, went back to my normal life, and got sick again. After more than a month in that situation, I decided to get a colonoscopy and endoscopy. From the biopsy of the samples they took, they diagnosed me with mild chronic superficial active gastritis. I'm already mentally prepared that it'll be a few months of diet.

The thing is, the symptoms I see in a lot of people, I don't have. My stomach doesn't hurt when I eat, I've only had a bit of heartburn twice in all this time. Although sometimes I feel a bit nauseous or dizzy, I feel my stomach bloated after eating and sometimes I feel full, difficulty burping, difficulty going to the bathroom (I have to strain a lot and what I expel isn't much) despite there being a lot of intestinal movement, and basically that's it.

The title is what it is because I don't know if those symptoms are more common than I think, but since I've seen that most of the typical symptoms I haven't felt, I feel pretty lost with the whole thing. Anybody that could help me?