What Was That?
 

About a kilometre into the morning commute today I heard a loud 'twang'.

Darn - broken spoke.

I just kept riding knowing that there was nothing I could do until I got home tonight.

Once I got to work I checked the bike over. No broken spokes.

I was annoyed when I thought that I had broken a spoke but at least I could sort it. Now I'm wondering what on earth that noise was.

Ah - the mysteries of cycling.

Could be a pebble picked up by the tires hitting the rim. I get that all the time.

That happens every once and a while with me too, I ride late at night, I hear it and think it is a stick or pebble, as I don't find a broken spoke.
I did discover, much to my dismay, my rear whell had gone kittywumpas on me. I couldn't do anything with it, so had to ride home, very carefully, knowing the squishiness in the handling wasn't my front wheel out of true, but the spokes of the rear wheel loose. I suppose this is a point to bring along a spoke wrench. May as well throw in the chain whip, spanner wrench...

Just carry an Alien multitool. :D

Hamstring?

Of course!! That explains the excruciating pain that started in my leg around the same time. I had just never put the two together.:D