Hello, I'm 5 weeks pregnant and sometimes have mild lower abdominal pa…

Hello, I'm 5 weeks pregnant and sometimes have mild lower abdominal pain, like during my period, but it subsides within 5-10 minutes. It happens 1-2 times per day. This is my first pregnancy. And I have intrusive thoughts that something might be wrong with the baby. How can I overcome my fear and is this normal at this stage of pregnancy with lower abdominal pain?