I have problems with both my achilles tendons and I’ll be the first to admit that I know nothing about this but………………
I have seen a physio who really does know about these things and apparently the worst thing you can do is to encourage bloodflow to damaged achilles tendons.They’re meant to be white because they have no blood flow to them. If they had a blood flow then they’d have nerves in them and when you consider that they have to take more shock loading than any other part of the body then you’ll realise that you don’t actually want to feel what’s going on down there.
If you are trying to mend damaged tendons then you might want to see a different physio?
Good luck, it’s a long process