Good morning forum

for the last 3 weeks my bowel habits have alternated between constipation and mushy stools. Some times the stool comes out too toned( dark brown soft but then second half light brown really soft. . Feel full in upper tummy and it swells up . Feeling generally uncomfortable around abdomen area . what mage me notice is a big ball of white mucus in toilet after going. Was diagnosed with stage 2A melanoma 40 months ago. Don't want to go to the doctor if it's nothing , but wondering if anyone on this forum has had similar symptoms.

thanks for reading