How to tell the difference between baby kicks and round ligament pain??

Kennedy • Married to my soulmate since 7.4.2020!💍💞 We have a 4 year old son, who took a year and a half to conceive! We are expecting baby girl March 11th 2021 after 2 1/2 years of ttc with fertility treatments 💖
This is my first pregnancy and I'm 2 hrs away from being 19+3 and I can't distinguish baby kicks between round ligament pain/dull cramps. I'm not sure what I'm feeling!! Any help?