6 weeks-unusual pain?

Kristen
I just made it to 6 weeks today. Yesterday I had really intense sharp cramping pain in my lower abdomen. I drank water hoping it was just dehydration. (I know I didn't drink enough water the day before.) It seemed to help. Then throughout the day, I had my usual sporadic, but light cramping and tried not to think anything of the earlier episode. 
This morning (one day after the single intense cramping episode), I woke up and my breast don't feel as tender and I feel less crampy overall. I don't have any bleeding, but I'm worried the loss of symptoms after such intense pain means I m/c. I'm trying to stay optimistic until my ultrasound in a few weeks, but I'm wondering if anyone else experienced something similar and things turned out fine? Thanks so much!!!