I would go for evaluation as soon as possible. Clotting with as can happen in any vessel.
I have primary as and quite a few other clotting problems hypercoagulation. I have not ben able to fly for twenty years since developing a large cot while flying on lovenox and aspirin as a precaution.
Last summer i flew again again with full doses of both lovenox and aspirin taken one hour prior yo flight time.
My husband and I watched rather horrified as in first half hour of the six hour flight from Atlanta to San Francisco a clot with accompanying pain and swelling began to form in groin and another more superficial clot behind calf on the same leg simultaneously showed up.
Needless to say I will not fly again. The 20 year hiatus from flying after the first clot experience was the correct thing for me. The one time experimental flight to find out if non flying status was over cautious showed that I was just being prudent.