I had early spotting with my first, due to a tear in the wall of my uterus. My job at the time required lifting 60+ lbs, and my dr. said that may have been a contributing factor. They put me on bedrest-no lifting anything, till the tear healed (3 1/2 weeks), then I was on a 20lb. limit the rest of my pregnancy.
If that is the cause of your spotting, lifting can cause it to worsen, so the no lifting advice should probably be followed. If a tear like that worsens, it can cause a lot of problems. Once you find out the true cause, you can adjust your restrictions.
I would personally arrange for a lot of extra help until you get a definitive answer.
I know how you feel, though-I've been on bedrest for both of my previous pregnancies-hoping for better luck this time around!