How do contractions feel?

Star • Mother of my first👶🏼 May 7, 2016. Insta// @BrasilianStar
I'm a first time mom & don't know I mean I went to hospital and they told me I was having contractions but it was just my stomach tightening  just a few minutes ago I felt really bad tightness and pain in my adomonial like if I'm getting punched and couldn't get up was that a contraction ?!?