Period like cramping (pregnant)

Is it normal? I just got a bfp and I’m so nervous because i’ve had reoccurring chemical pregnancies back to back and it’s been 5 times that I’ve had a chemical. Now I’m cramping and I’m afraid that it’s going to be another one. I just bought prenatals but i got the one that has no iron, and I feel like I need one with iron. I’m supposed to be 3w5d, I got a positive test yesterday and I still have my sore bbs from the time i ovulated to now. I’m just so afraid to have another chemical. Cramps aren’t bad but I’m just worried that it’s going to be another chemical :/