Hello. I have a tiny hard colorless painless lump on the tissue of my anus today. I went drinking 2 days ago, woke up with a stomach ache (which i think is normal...), slept, went to work, my body didn't accept the food, then came home and got a strange pain near my uterus so i ran to the bathroom (i also have constipation even though i ate a lot of fiber today...) and felt the little lump. what can this be? do i need to worry? will it go away? thank you for your help in advance.