As Msvjv Suggested------seek out a hemotologist...that can run a multitude of test to diagnosis you clot formation and make recommendations. I'm so biased re Eliquis.........just spent 8 of of the most miserable months of my life on Eliquis after being changed from Warfarin. Tons of case studies re Eliquie vs Warfarin where Eliquis gets the short end of the deal. Physicians like it because there is no monitoring required as is with Warfarin. I spent 8 months with Vertigo, dizzy spells (sometimes 3-4 per day), migraine type auras but no headaches. I finally found a piece of research done in 2023 thru NIH that indicated the pros/cons of Eliquis. Sound like you need to travel to one of the large teaching institutions, Mayo, John Hopkins, Duke for a thorough workup. Something does no sound right! And where may I ask......where was the source of the clot? I say this all as I have been stuck on a blood thinner since 2005 because a young Cardiologist "thought he saw a shadow on my atrial appendage." Now no one has the appetite to be responsible for taking me off "just in case."