5w5d ultrasound and hcg levels?

I should be about 5 weeks and 5 days pregnant today. The first date of my last period was 12/2. I was fertile 12/11-12/17, ovulation on 12/16 (according to my app). I had bloodwork done on 1/5 where my hcg levels were 338, transvaginal ultrasound on that day showed nothing. Repeat bloodwork on 1/8 and hcg was 1300. Repeat today (1/12) and it was 3300. I had an ultrasound today which showed only a gestational sac, no yolk sac. I am freaking out because I feel like the hcg is lower than it should be/ not rising enough (even though it is technically in the normal range - at this time with my daughter, my hcg was in the 12,000’s) and typically you see a yolk sac around this time. Anyone else ever have this happen and have a healthy pregnancy? I have another ultrasound in 1 week, but I’m going to be a mess until then. :(