2 wks after iud insertion, i have been bleeding/spotting (there is a variable amount of blood for light to heavy). rx was sx - what should i expect?

It depends.: It depends on the type of IUD, whether you're having any pain, whether the IUD was inserted during a period, etc. Spotting after IUD insertion is common, and moreso if it wasn't inserted during a period. Usually bleeding and spotting will get better and resolve over time. If you're having pain, then I would see your doctor, since it might indicate infection, which would require antibiotics.