36 weeks ftm need help!

Can someone explain what contractions feel like please? I’m a young ftm and have no idea what to expect! Also don’t have a women figure in my life to ask and i asked my doctor but all they said was i will know. I just want to know what to expect because Iv been feeling very crampy and sharp pains and dull ones as well!! All the details would be much appreciated!❤️✨❤️✨❤️