When to worry about cramping?

Honesty • Engaged with our miracle daughter after being told I could not get pregnant.
Hey sorry if this gets asked a lot, I tried googling but the results were unhelpful. I'm 16 weeks along and I've been stressed a lot lately. I've noticed when I get stressed badly I can feel butterfly movements that for lack of a better way to describe them, they don't feel happy. It feels very tense I guess. Today I took a nap to calm down and woke up from cramping. There's been no blood, but I've only been up about a half hour and the cramping has been fairly consistent. Should I be concerned that it was bad enough to wake me up, or should I be alright since there isn't any blood?