Am I having braxton hicks?

I'm 19weeks+2days and I've just got back from work and relaxing on the sofa when all off a sudden I get a massive pain in my stomach where the baby is. It lasts for atleast a minute and has happened twice now. It feels like really bad trapped wind but a lot more painful and I know it's not trapped wind (tmi) lol! Is it braxton hicks or something I should be getting worried about? I'm a first time mum aswell so not experienced it before. Many thanks 😊