What Causes Stomach Ache Along With Diarrhea And Constipation?

Hello, I have been experiencing some irregularities for some time now but they have recently gotten worse. These symptoms include stomach aches, cramping, as well as diarrhea, sometimes constipation, bloating, fatigue and general tiredness, and I get full really fast when I eat. I have noticed that it is significantly worse when I drink coffee, or eat macaroni and cheese for some reason so I thought it might be a dairy or lactose intolerance but sometimes it doesn t worsen after consuming dairy. I feel like I have been using the bathroom way more than I used to and its weird because after using the bathroom I often still feel like I have to go.. Some other facts about me in case it helps is that I am a 19 year old female, I have generalized anxiety disorder, sensory processing disorder (including sensitivity to tastes and textures of foods), and eczema Please let me know what you think this might be and how I can alleviate it, I am currently confused :) Thank You!