Spotting on and off?

How normal is spotting? I'm about 10+4 weeks and had some spotting a couple days ago and just started spotting again today. Nothing major and no cramping but my uterus feels heavy? I assume cuz there's a baby in there lol its not heavy bleeding but I haven't had sex in almost a week and have been really just taking it easy. Normal? Or should I be more concerned? I went to the Dr on Monday when I first started bleeding and they did ultrasound and blood tests and everything looks normal im just paranoid