Cramping early in pregnancy

I had a miscarriage in August of 2018. I was having alot of cramps and I was very stressed which eventually led to me losing the baby at 5 weeks. I took a pregnancy test 4 days ago and it came back positive. I should only be around 4 weeks ( I haven't gone to the doctor yet). I have been having cramps again but not as severe as last time. Is it normal to have crapms in early pregnancy?? I have been having alot of pressure built up in my back and stomach from gas. Could that be the cause of my cramps? I am nervous something may be wrong.