OP - I had something similar. I had weird chest sensations so my doctor ran a d - dimer test to rule out a PE. The d dimer test was positive but my doc said he didn't think I needed more of a work-up. I remember googling and ended up just letting the positive result go.
This is what I Googled:
False positive readings can be due to various causes: liver disease, high rheumatoid factor, inflammation, malignancy,trauma, pregnancy, recent surgery as well as advanced age.