I can't answer to the blood clot- but a hysterectomy does sound a bit extreme considering you are still in a watch and wait period. I would get a second opinion. Usually a LEEP procedure is done first etc. I have only heard of hyserectomy even being an option if a woman has already had all the children she wants and then decides she doesn't want to deal with the constant cervical checkups or possible reoccurences so to speak. It all sounds a bit strange though as you are talking some major surgery there- so I vote for getting a second opinion.
As for having HPV for so long without knowing, I had mine for at least 6-7 years, possibly more before it developed into abnormal paps.So it can stay in your body a while before leading to anything. I also have a high risk strain that developed into severe dysplasia, but I just got a LEEP done- had a great surgeon with lots of practice in this area. I only had cramping after the LEEP for the first hour. Then that was it. Although the mental stress and emotional upset was my real battle during those first few months of finding out. Now I am testing negative for the virus- which I think is really neat.
Anyway, just don't despair and get a second opinion if your doctor is pushing for the hysterectomy. He could just be throwing it out there as one of many options though.