What Causes Twitching Feeling In The Buttock?

Hi, I'm having a problem in the buttocks area. I constantly keep squeezing my buttocks in and it hurts. It keeps me up at night when I'm trying to fall asleep and is really uncomfortable when I'm sitting down. I was wondering if this is just a twitch or if I'm thinking about it too much that it is causing me to do it. I would also like to know if it is cause I am injured or have any health issues in that particular area. Thank you.