Breathe! You are not dying. It’s not an unusual reaction to finding a lump, or anything else suspicious, but it’s way premature. The lump may not be cancerous. Even if it is, it’s small, treatable and the prognosis may be very good. It’s not remotely what you want, and your family history will naturally make you a bit nervous, but well done for keeping up annual tests. It puts you ahead of the game - early diagnosis and the many advances in treatments makes a huge difference. Have you family and friends who can support you, particularly right now? Any help to get your mind at least temporarily onto something else would be good. Temporary help
to reduce anxiety and let you sleep is a good thing. Just keep breathing slowly......