2nd ultrasound today. 8 weeks 1 day. Can't seem to shake this anxiety!

I had an early ultrasound last week since I had a blighted ovum in January. Found a heartbeat, heart rate of 132! Was the most exciting and wonderful thing. A couple days later I started having minor brown spotting and little cramps, in addition to a major decrease in the nausea. So I called my midwife and they decided to do another ultrasound today. Heartbeat still going strong at 169 today and the little dot turned into a bigger blob with little arms! Amazing what can happen in a week. However, I spotted again today after the ultrasound, this time red, and still have cramping. Even though I literally just saw that everything is going well in there, and I was told the cramping sometimes just is from your uterus stretching and bleeding sometimes just happens for no reason but doesn't mean anything, and nausea can ease around this time of the pregnancy for some women... I can't seem to shake this anxiety that something bad is going to happen again!