Possible irregular contractions??

Alright so I’m 33 weeks, for the past week and a half I’ve been noticing my son dropping rather quickly and consistently. I’ve also been having tightness in my lower abdomen along with pain like cramping and lower back pain and feeling nauseous when this happens multiple times a day. Is this normal? I’m a FTM so I have no idea if I should bring this up to my doctor or if this is normal at this point. At my last appointment she wanted to get another ultrasound because my son was measuring ahead based off my fundal height but I won’t have that until I’m 35 almost 36 weeks. I don’t know if I need to call a nurse line and let them know or if it’s normal and just need to suck it up lol. I kind of mentioned it at my last appointment but didn’t get to fully explain that it was tightening and it occurred multiple times a day (I was just casually talking to the person who does your weight and preps you for the actual doctor) and she said it’s just round ligament pain but I don’t feel like this is. 😂