Ectopic Pregnancy

I have stage 3 endometriosis so my dr said I am a high risk for an ectopic pregnancy. I am 4 weeks 3 days today. I seem to have good line progression on the pregnancy tests. I had an ultrasound today but they weren’t able to see the baby yet (which the ultrasound technician said is not abnormal for this early on). I haven’t had any abnormal cramping or bleeding. Can anyone give me an idea when I would know for sure if it was ectopic, if so? Any advice at all is helpful, because this has been extremely stressful 😫