Uterus pain?

Lainey • Due with Baby #1 Nov. 2016!
Okay ladies I have a question. I tend to think I'm worrying too much here, but I'd really like some reassurance. This is my first pregnancy so all this is new to me.  Im a little over 7 weeks pregnant with my first doctor's appointment next week. Everything seems to be going fine - continued HPTs still show I'm pregnant, and I haven't had any spotting or bleeding. My worry is the intermittent dull/aching/sometimes shooting pain I feel every once in awhile in what I think is my uterus, except it feels a tad off to the left of center. It's not really painful, just bothersome, and of course it has me worried about miscarriage and ectopic pregnancy. Anyone have any thoughts/experiences with this?