Both of these illnesses are quite common in hedgies & must be treated as soon as it can be to avoid further health issues.

Constipation:

You can tell if your hedgie is constipated by feeling belly & if its hard they are more than likley experiencing constipation. Other signs include, dry, misshapened poos, & not eating or drinking as much. To help cure your hedgie of this uncomfortable illness, put him/her in a tub of warm water for a few mins. If that doesn't loosen things up then you can try giving a touch of apple juice, fresh fruits, prune juice, or unseasoned pumpkin pie filling. If NONE of that helps, get your hedgie to the Vet. ASAP! If your hedge has a blockage the Vet, is the ONLY one that can diagnose & treat the illness.

Diarrhea: 

If your hog has a case of diarrhea & there will be no questions of this, their poo will be soft, mushy, & or discolored. You will want to get this treated & cleared up right away as having diarrhea will cause for dehydration. You need to first of all figure out why the hog is getting sick.. could it be food change, water chage, more added stress? The best ways to solve the problem is to give a few drops(one or two) of Imodium AD. This should fix the problem, if it doesn't give plenty of fresh food they are used to, & maybe try a few crickets & or meal worms. If the diarrhea comes back, take your hedge in to be sure there is not something wrong with the intestines & or bowel.