Erika, I was thinking about your question as to how you should go about increasing your distance to reach what you were doing before your last flair.
Honestly I don´t know and I wouldn´t listen to me but maybe by not pushing it and only going to where your body feels comfortable might be what I would do in your situation. When your body feels strong enough to go back to the greater distance you´ll feel it. My experience of pushing this condition is detrimental and I end up in a worse state than before. That is my ha´penny bit and nothing else.

Did another 2000 metres today in the pool.

My back has been at me ever so slightly since christmas and I am trying to keep to only that by swimming and taking the medication. Some say that my medication stops having the same effect after a few years so maybe thats the problem since I have been on it for 5 years now or maybe since I lost my main income I have been running around trying to make up for it and my exercise suffered and then my back started at me. I don´t know, but I feel better when I am swimming so at the moment I am trying to swim as much as possible.

That´s a long winded answer if ever I saw one