Shooting pain ? 13 weeks

Alyssa

I have a really bad shooting pain in my left buttock. At first it started off as a cramp but now it's getting worse to the point I don't want to stand walk or even sit down , I just want to lay down . The pain is constantly there now and the pain is slowly making its way down my leg . It hurts so bad to the point my leg feels like collapsing. Never had this problem during my first pregnancy any idea what it could be ?