For another perspective, there's really nothing you can or can't do that will keep you from spotting if that's what your body is doing during the first trimester (subsequent trimesters are different, I think). Spotting is usually implantation bleeding that has been stuck up there and got removed due to some sort of activity or it's the result of a sensitive cervix that bleeds when hit or when there's pressure put on it. Neither of those things will harm baby in the slightest so there's really no reason to stop doing something just because you're spotting. The only reason would be if it will make you feel more stressed or upset then by all means stop doing those things. Because in reality if you're bleeding and it's a miscarriage no lack of activity will make it stop and if you're bleeding as a side effect of implantation bleeding or a sensitive cervix then no activity will make you miscarry.
Hope that helps and good luck! I spotted during the first trimester for both my previous pregnancies and have two healthy daughters to show for them.