Blood clotting problem. what could it be? how long do the tests take to figure it out?

Blood clot: If you are referring to blood test/ work-up, the results should be back within 2 weeks, in general. There are many factors that can make people to have blood clot- such as - post surgery, obesity, being on sterids or other medication- hormone/ ocp, testosterone, chemotherapy, cancer, hereditary problem/genetic mutation, etc, ). Wait for the result and discuss in detail with your hematologist.