sharp pains. straight down leg

This is the second night this has happened I'm 26 weeks along and  I start to have sharp pains in my uterus that no matter which way you move it just get worse it going down my leg too  I'm in tears as we speak. Idk what this is but  I also feel like I need to puke i don't think that the pain was so instense but yes very painful. What is this please help just don't read and ignore I need to know if this is something serious