hi Rain, i had surgery the day after you (11 july) and suffered terrible tummy and shoulder pain but the lady in the bed next to me was absolutley fine! i suppose it's a very individual thing, but the gas seems very reluctant to leave my abdomen! and that's probably what is causing the pressure on your chest but it is early days and we must be patient (even though every day feels like a week!)
i wonder if you may have eaten your soup too fast if you keep burping it up?