What Causes Abdominal Pain After Eating Spicy Or Greasy Food?

hello doctor, I'm 19 years old and I've been very stressed. I'm busy all the time from planning a wedding and lately whenever I eat spicy or greasy foods, I get really bad abdominal pain between my navel and the lower part of my ribcage. Basically right in the center of my stomach. It happens about 45 min after i eat. Sometimes I have to use the bathroom from the pain, and sometimes i dont. Either way the pain doesn't dissipate until about an hour later....sometimes more. I've been trying to eat healthier and bland foods to relax my stomach, and I've been eating smaller meals throughout the day, but it doesn't do much. I've lost my appetite and I'm tired all the time. Also too I'm noticing I look a little pale and at night sometimes I feel a little nauseous. And my urine is darker than usual, even though I drink water most of the day. What is happening to my stomach? Or is it even my stomach that's the problem?