Thrombosis Symptoms I Have These Symptoms, No Diagnosis From Doctor Yet, What Can It Be?

I have these symptoms, no diagnosis from doctor yet, what can it be? - thrombosis symptoms

I went to four doctors and none have been able to diagnose what I have. What are the symptoms that follow, I am confronted with:

Feeling weak and difficult to both legs;
The instability in both legs;
Pain when my toes.

I have tried to prove that, if it is possible for thrombosis, but the symptoms are not quite what I know. Has anyone any idea what could be? Thank you for your help.