Colostomy output one month post op

Hi
On sept 21 i had colostomy surgery due to diverticulitis blowing a large hole in my colon. Not just a perforation. So im doing fairly well. But this eating business is getting me down. I eat oatmeal and drink prune juice every morning. I also use stool softeners. But every day i fight constipation. I am also on pain meds for chronic condition. I know its partly the pain meds causing this. But i truly dont have much of an appetite yet. I get full on half of sandwich or half of anything I used to eat. I limit bread intake. I wait half my day for output. This is just ridiculous.