Thanks everyone. As AI is so much in the news I asked it the same question and this is what it came up with…
It's possible that you're experiencing a condition called Raynaud's phenomenon or Raynaud's disease. Raynaud's phenomenon is a disorder that affects blood vessels in the extremities, particularly the fingers and toes. It causes the blood vessels to narrow, which restricts blood flow and leads to changes in skin color.
In Raynaud's phenomenon, the fingers and toes may turn white, then blue, and finally red when the blood flow returns. Exposure to cold temperatures or emotional stress can trigger these episodes. In your case, it seems that your toes are reacting to temperature changes by becoming red or purplish.
While Raynaud's phenomenon can occur on its own, it can also be associated with other underlying health conditions such as autoimmune disorders, connective tissue diseases, or nerve disorders. If you haven't done so already, it would be a good idea to consult with a healthcare professional, such as a primary care physician or a rheumatologist, for a proper evaluation and diagnosis.