3 weeks ago i had extremely high d-dimer of 8330 ng/ml. 3 days later: 904. can i have had a pe or dvt without knowing and without sequelea?

No symptoms is good: The apparent lack of any symptoms of a pe or DVT is good news, and makes it very unlikely you had a significant pe or dvt. The d-dimer test is very sensitive to recent clotting of blood, but it is not specific. That means a high level can be caused by many things. Just drawing a patient's blood a couple of times has been know to raise the d-dimer above the normal range!

High d-dimer: As dr. Accurso said, d-dimer levels are only helpful when you don't have a blood clot. If your d-dimer level is zero, you can rest assured that you don't have a clot. Otherwise all bets are off. D-dimer is an acute phase reactant, meaning that anything that causes inflammation can raise your d-dimer level. The good news, if your did have a clot with a d-dimer of 8330, it would have been big!