Very painful cramps

I'm 4 weeks and I've been very bloated, constipated and gassy.
But the last two day I have been feeling some awful cramps in my lower abdominal area. I can't tell if they are intestinal or something else. I woke up at 4am last night and spent over an hour curled up in a ball in pain. 
This is my first pregnancy. 
Is this normal ?