This rarely happens to me, but it happens to me as well. Sometimes, it's because I haven't taken a shower in a few days or sometimes I've eaten too much spicy foods and that's when I just drink a lot of cooling liquids. (Water, Ice Tea, etc.)
For the past couple of weeks, I have had most of the symptoms I am reading about here. My problem started with constipation, followed by anal fissures, then a burning sensation inside my anus. Hydrocortisone cream (over-the-counter) helped if I applied it several times a day. You have to rub it around inside the anus. Then, I started eating bran muffins and drinking several cups of coffee to get rid of the constipation. Today, I'm doing very well; the soreness is almost completely gone. What a relief.
Have you eaten something in the last 3 days that you usually don't? Certain types of food can cause this and an OTC Hemorrhoid cream will usually clear it up, sometimes overnight. It has to be a cream, though, not the gel and not suppositories.
Good news !
My symptoms are gone. What did the trick, was just 2 applications of plain old green Aloe Vera gel. It's available over-the-counter near the sun tan lotions and hand lotions. I rubbed it around, inside and out. I hope this works for everyone else.