Why Does Part Of My Rectum Protrudes Slightly With Itching And Tenderness When I Go To The Toilet?

Hi, over the past few weeks when I go to toilet it seems the inside of my rectum comes out a bit. and I could push it back in. there was also some light itching. I thought it was an injury so I stopped straining when I used the toilet and the past few days it sort of reduced but my anus has felt tighter. Today, a little bit of my anus came out again and I tried to push it in but it was a bit difficult as my anus felt a bit tender and dry, I did my best and washed up. this evening I felt very intense itching that I had to go into the toilet. I wet my anus and pushed the tiny part of it that was outside back in. Please what could this be and what can I do?