Nausea subsiding at 10 weeks?

Hi everyone,
Up until 10 weeks (2days ago) I had some nasty pregnancy symptoms like all-day nausea (without ever getting sick though), headaches, extreme tiredness, tender breasts, food aversions etc. and then once I reached the 10 week mark two days ago my nausea is 99% gone and I've also felt less miserable with the rest of my symptoms. This is my second pregnancy and with my son I never really felt morning sickness and felt great in general (even in the 1st trimester) so feeling like a zombie for almost three months straight is new to me and I'm freaking out wondering if something isn't wrong with my baby since my symptoms have subsided- I know ms is supposed to usually go away at 12 weeks but that's still almost 2 weeks away. Had an us at almost 9 weeks and the baby was doing great- heartbeat present, moving arms and legs even, measuring right on time. My next us is this coming Thursday but I'm just a nervous wreck here stressing out about suddenly feeling more human and alive again. Please share your experiences and thoughts with me. Thank you!