Unfortunately, if you are coughing up blood and concerned about blood clots in the lungs, you absolutely must go to the hospital. I understand your reluctance, but there is nothing that you can do at home. This is potentially a life threatening problem and needs immediate evaluation. The warfarin level might be too high and causing bleeding. This can be corrected in the hospital. If you are having blood clots, your warfarin level may be too low or you may need a different kind of treatment. In any case, it is critical to know specifically what is going on to start the correct treatment, and the only place this can be done is at the hospital. Please go to Emergency immediately. Hope this helps.