Cramps!

I have had extremely bad cramps all day yesterday and their still happening today. I am 21+2 weeks along and I have a appointment tomorrow. And I am trying to hold off till tomorrow if I can. I don't know why I have such bad cramps, I have no bleeding or abdominal pain accompanied with the cramping. I was told to drink water since I don't drink near enough or that I may have a infection or a uti. So help please opinions on if I should go to the hospital today.