Hi y’all!

I went in today for a TV Ultrasound. Slight intermittent cramping nothing more than what feels like gas pains. Scant amounts of brown discharge when I pee and wipe every so often. Like a drip or two. LMP I have written down as Jan 31 but I have irregular periods and very short cycles so I don’t actually know when I would have ovulated. Estimated 6weeks 4 days and my TV ultrasound showed a sac 1.27cm but nothing in it. Waiting on Hcg levels from bloodwork and will repeat in 48 hours to see a trend… has anyone seen the yolk sac or fetal pole show up later than 6/7 weeks?? Perhaps I’m just too early as conception could have occurred later than I think… ?