past week only, eaten considerable amount of refined/ fatty acidic food. Soft stool yestrday woke up wiv intense stomach cramps. Will I develop gerd?

Hard to predict. GERD is triggered by many things including diet. Caffeine or nicotine, reclining after meals & acidic foods are all contributing factors. We are all capable of having "heartburn" on occasion but true GERD is a pattern that only some will develop. Your change in diet sounds like a contributing factor to your symptoms. Time will tell.