Belly Cramping/Muscle aches 8wks4days

Okay soo I am 8 weeks 4 days with our first baby so I am new to the whole pregnancy world. So far things have been smooth, just exhausted, and no vomiting (yet lol). We had our first ultrasound and the doctor said baby C looks great and has a healthy heart beat at 155. I have been having some cramping which I have read is normal as the uterus expands and no spotting. BUT, the cramps are more in my abdomen and feel muscular, almost like I did too many crunches and when I move they feel like they're pulling. Has anyone else experienced this? My sister said she did but when she was further along. She's due August 6th.