Can you tell me in january, they done just a ct scan on my lungs and showed nothing and sent me home. i had accurate is the d-dimer for clots?

Not accurate : A negative d dimer is helpful for ruling out pulmonary clots. A positive d dimer is basically useless as it can occur from a variety of reasons. A CT angiogram is close to the gold standard for determining whether there are clots in lungs. Regardless of what the d dimer showed, if the CT was negative and they used contrast for the CT then you are in the clear.