I am Week 4 Day 5 currently and also had light bleeding. Just went for ultrasound and also no gestational sac found. Blood test result came back at HCG 400 so I guess normal to not see anything on ultrasound? waiting to repeat again on Monday to see if the numbers rises properly. Fingers crossed.
am going through first pregnancy so i couldnt give any advise but deeply hope everything is fine on your side 🙏