I am injecting diamorphine im daily for past 2 months for severe spinal pain i have cauda equina. i'm worried about the lumps going to blood clots?

Unclear question: What lumps? If you are developing lumps at the site of injections, it may be due to faulty injection technique. The risk of blood clots, from what you described, is not great, however, you may be risking infection from injections if you are not following a good technique. It would be prudent to consult the doctor who prescribed the narcotic. Wish you good health!