Third Trimester Cramping

Well I've been getting cramps in my lower abdomen lately at 33 weeks now. A few times a day. Doctor suggested it's Braxton Hicks but it hasn't felt that way to me. The cramps have been below my big belly, mainly to the right. Well today, my kitten darted out the door earlier today and I had to chase after him. Now the cramp won't go away. What could be going on? PS here's a few pics of my little kitten, he's so cute how could I not share?!?!?