Braxton hicks vs contractions

How can you tell the difference between Braxton hick and contractions? I am 34 weeks and 5/6 days and keep getting a tightening in my lower belly(have been for a couple hours). They aren’t really painful, just making me nervous. This is my second pregnancy and I am way more anxious compared to my first. I can even feel the tightness when they are happening. With my first my water broke so labor was super obvious. I don’t want to be that person that goes in for nothing but if it is something I don’t want to be at home (especially since it is fairly early).