Is pain in the leg caused by blood clots worse with movement or non movement or does it vary?

Worse with movement: I am not quite clear on your question, but if you are asking about pain after a blood clot, and worse with or without movement, pain is usually increased w/ movement. If you are worried about having a blood clot, you should go to the er, especially since you mentioned "breathless" in your conditions and this could represent a complication of a blood clot, a pulmonary embolism which can be fatal.

DVT: Deep vein thromboses of the lower extremity could present with any of those scenarios. There is usually a notable swelling of the lower extremity.