What do Braxton Hicks Contractions feel like?

Kenia
Im a teen ftm and im 33 weeks. Ive been feeling this tightening pressue in my pelvic area that tightens for like 30 seconds and then looses up and starts again. it happened like 3 times in 20 mins. i think its braxton hicks but im not sure since this is my first baby. did you have braxton hicks at 33 weeks ???