PREDNISONE ;Been prescribed to take Prednisone for 28 days, am I at risk for serious side effects?

Just diagnosed with Crohne's disease in the small bowel. My disease is a pretty mild case however. I am a very healthy young man and my only problem is severe cramping in the abdomen which occurs about once every 2 weeks. The Doctor prescribed me prednisone for a 28 day period (starting at 40mg a day to finally10mg). After reading some horror stories about this drug (moonface, withdrawl, acne, etc.), I am wondering if the cost out weighs the benefit. Can major side effects of prendisone happen after taking it for only 28 days? With a mild Crohnes, are there other ways to contol this disease without prednisone? Any insight about this drug would be greatly appreciated. Thank You!