weird sharp abdominal pain

I've had this for a longtime now, the thing is when I would sit down for a while (maybe like 1-2 hours) watching tv or whatever and my stomach would be a little squished or compressed, and when I would stand up it feels like something on my left side is being pulled down or being teared..and it really hurts, like when I try to pee i can't evacuate it all cause it feels like something inside me is being reaped and if I press on my left side it would really hurt like almost a super bad cramp from the inside, and I would have to lay down and not move too much to make it go away..anybody know what itcan be? 😞