Aiyah, spotting after HVS is super common lah, cervix tu sensitive je, especially when pregnant, so the swab can cause a bit of bleeding. Tapi since you're only 7 weeks, it's still good to just check in with your doctor to make sure everything is okay, especially if the spotting continues or gets heavier than a bit of brownish discharge. A few of my mum friends had the same thing and doc reassured them it was nothing, but better safe than sorry at this stage, kan?