Losing to yourself totally sucks.

If I hadn't recently started developing this competitive streak, I seriously wouldn't have given two hoots to what happened to me yesterday. But right now I'm seriously annoyed at having to abandon my 20 mile walk 5 miles before the end.

Everything was going well to start with. I bounded off towards the Thames and bounced along the Southbank. Even as I headed up through to Angel and onto the Regent's Canal tow path I had a bit of a spring in my step. I took a phone call from my husband 2 3/4 miles from Limehouse, and proudly proclaimed that I was on course for an early finish, but by then the ache in my hip had already set in.

By the time I'd left the canal and was heading onto the Thames path near Westferry I was talking to myself (OK, swearing to myself) but had made a pact that I'd keep going whether it hurt or not.

And then I passed a tourist who was looking at me with a look of bafflement across his face. I don't know whether he was trying to translate some of my choice language, or whether he genuinely questioned why I was continuing to hobble on when I was clearly in some pain, but he helped me get some clarity on the issue.

I looked awful. I felt awful. It was time to quit and get some help.

I tearfully jumped on the DLR at Westferry and went home. I'm going to be having a chat with a physiotherapist sometime soon to see where I'm going wrong. I felt, and feel, like an absolute loser, but I'm trying to comfort myself with the reminder that this was just one walk. There are many many more 20 miles to cover over the next 8 months.

Oh crikey, I hadn't thought of that.