If you are able to press on it without much pain, then it sounds like a prolapsed bowel, uncommon in
young people with no children
, but still worth getting checked out, you dont want to have that problem forever :)
Ive recently had similar issues to all you ladies, but my tests have come back clear, clear blood, urine and smear... But agony to sit down, masses of preasure and swollen and painfull to try pass stool. scary as it is within the skin and unable to see.