Cramping. Really worried.

Im currentl 5 weeks tomorrow. Is it normal to have cramping and light back pain? Ive had cramping almost period like foe the past week almost. Off and on. Usually lasts a few minutes and will go and vome back every few hours. Today its worse. Its been contant for about 20 minutes. No bleeding. Very sore breasts. Awful fatigue. Heartburn. Nausea. And mood swings. My peogesterone level they said was outstansing. I had a miscarriage 7 months ago though and the cramps are worrying me. Can you tell the different between normal cramps and dangerous cramps??? Very nervous.