They are veins that hurt so bad when pressed upon that it can paralyze your thoughts and whatever else you were doing. They are veins on the rectum that swell up related to pregnancy or constipation.
So wat is a hemoroid? I kno its on your bum lol..but thats all I kno. I know this has nothing to do with your question..sorry. I havent had that pain but I have plenty others! so sorry for you tho..i hope you find relief!
Ive been taking baths seems to help.
Heating pad might help if you have one. I have been using mine every day because of a pinched nerve in my back,hemoroids(sorry tmi), and my spreading hips. Just where ever the cramp or pain is at I put the heating pad on.