I've noticed my belly is getting rounder

I don't know if I'm pregnant or not I took a test yesterday and I'm not really sure about the results i saw a light line but it was a clear blue so I'm not sure... anyways I would be about 5 weeks if I am. But I'm noticing that my belly is changing. I'm not losing any weight it just looks different. This would be my second pregnancy. What do you think?