Go through these in order and stop at the first one that applies. If you are reading this for someone else, answer for them.
Stroke symptoms, severe breathing difficulty, significant chest pain, coughing up blood, fainting, or uncontrolled bleeding require emergency care.
New one-sided leg swelling needs urgent assessment.
Routine follow-up helps the care team review clot prevention, bleeding risk, pregnancy plans, cardiovascular health, and any associated autoimmune disease.
Care may involve primary care, hematology, rheumatology, neurology, or a high-risk pregnancy team.
Routine appointments are appropriate for medication questions, mild side effects, pregnancy planning, or discussion of future clot risks.
The article also says
People taking warfarin need regular clotting tests and medication reviews.
Monitoring may be more frequent after a dose change, illness, or the start of another medicine.
A later negative antibody test does not automatically mean treatment can be stopped.
Contact the treating team before surgery, dental procedures, long-distance travel, pregnancy, or starting hormonal medication.
Anticoagulant treatment may need advance planning, but it should not be interrupted without instructions.
Every sign above is quoted from the sofidex article on Antiphospholipid syndrome - APS. If you are not sure, err upward — it is always reasonable to be checked.