Thanks, bbp, I think that things have settled down now. I'm still waiting for the results of some tests done a few weeks ago, but it looks as though everything is (finally!) back to normal - I started training again just over a week ago - my first time since November.
I've lost a lot of fitness, stamina and speed, but it's a relief to be back out there, so I'm just going to take it easy and see how things go. I had hoped that I'd be able to do the NF mara in September, but that might be a bit optimistic.
There's a lot to be said for HR training
