6 week ultrasound ... help!

Hoping some people have experienced this ... went for my 6 week ultrasound today (6weeks and 5days) I took clomid for pregnancy so they do an early ultrasound. Baby’s heat rate looked great at 113 bpm. Anyways there was a sac like of fluid a “pocket” of blood he called it... he didn’t seem concerned and said it happens in 30% of pregnancy and it usually just goes away but I may see some dark brown spotting ... has anyone else been told this? I have another ultrasound in 2 weeks to check again the pocket was 3mm

Thanks!