Back home from the ER.
Turns out, it's not constipation; chest MRI and urine sample testing turned up nothing wrong. My stabbing pain seems more to be muscle cramping from attempting to pass my bowel movements; maybe stool softeners will do the trick. ER doc prescribed some acid reflex and nausea meds and referred me to another doc for further investigation. Also recced more fluids for dehydration. Will also notify my personal doctor on this.