Yesterday i noticed a little blister on one side of anal area. Today it grows a little bit. I also noticed another tiny blister on other side of anal area. No pain while pooping and no bleeding. It pain a little bit when i press it. I have a history of anal fissure but it's been a year I was fine. I dont have constipation issue right now, I poop 2-3 times a day . I drink a 2-3 litres water, exercise daily and eat fruits&vegetables. Can anyone explain me why it happened?