Sudden increase in stoma size and some pain

Last night when I changed my appliance I noticed that my stoma appeared bigger. Not longer, but thicker, a wider circumference. I changed the appliance as usual. Today I noticed some internal discomfort below the stoma when I bent over. So tonight I changed the appliance again. The stoma was still big but otherwise appeared normal, no discoloration or changed length. It now measures 1.25 inches instead of my usual 1 inch. I cut the pouch to 1.25 inches and put it on, but it really hurt when I pressed down to attach it. Right now I'm lying down and in no pain. Any ideas? My surgery was 9 months ago and the stoma hasn't changed size in 8 months.