The one where I break the cardinal rule of marathons...

 "Nothing new on race day"

Most people who have done a marathon share these two rules:

1. Pace yourself, don't go off too quickly at the start
2. Nothing new on race day (no new shoes, clothes or food)

The first rule wasn't too difficult; the group that I started with was large and not particularly fast, so I managed to track my target pace on the Garmin.... all good.

Turning into Woolwich, the emotion set in, crowds of people lined the streets to cheer us all on. Kids giving out high-fives, pubs blaring dance music from their windows, bands playing to the masses and strangers handing out sweets, slices of orange and encouragement.

This is when you forget the nerves and settle into your rhythm, all of your training has been for this, and it's a chance to enjoy the fruits of your labour. 

As you know, I'd written the names of cancer-battling loved ones on my arm, one for each mile, and as the race progressed, I developed a system of checking the name each time I ran under a mile marker. This kept my spirits up and reminded me what this is all for. 

Nathan had the genius idea of circling the miles where he would be waiting with Erica. This REALLY helped, it gave me something to look forward to, and the hugs were precisely what I needed. 

Tower Bridge is roughly halfway, and this is a game-changer. As you turn the corner to cross the bridge, the noise of the crowds hits you like a train, people scream your name, the sun is shining, and London looks incredible. I'm getting choked up just thinking about it; this was the high point of my race. 

After Tower Bridge, you turn right onto the highway, you hit mile 13 and come face to face with runners going the other direction who are hitting mile 22. They look tired, and they're the fast ones; what the bloody hell have I signed up for?

People warned me about mile 14; this is when the roads narrow and you head towards the docklands where there will be fewer crowds, and the legs will start to ache. I'd been regularly taking on energy gels and water but spotted a Lucozade station and thought, "it's a mass-market drink, I'm sure it's fine" that was a stupid thing to do.

I genuinely don't remember anything about miles 15 to 18; I remember reaching mile 19 and thinking. "I don't feel so good". I will spare you the details of what happened next; suffice to say that the portaloos don't have toilet paper, and I lost a considerable amount of time trying to sort myself out.  

Through Poplar, I started to feel better, I was told to look out for Run Dem Crew at Limehouse, and they did not disappoint. 

Next up, the Limehouse link tunnel. Someone said, "we don't talk about what happens in that tunnel". It appears just after mile 21 and sucks the life out of everyone who enters. 

There are no crowds; it's hot sticky, smelly and full of people who, like me, wonder what the f**k they were thinking signing up for this. 

.... and then you hear the band... they're at the exit of the tunnel... drawing you away from the despair and closer towards mile 23 "... hang on... why does the marker say mile 22? 

Shit.... my Garmin says I have done 23 miles..." I had forgotten about this, you run further than 26.2 miles on marathon day as you're weaving around people, finding toilets etc. 

This part was challenging for me, one extra mile doesn't sound like much, but when your legs and lungs are screaming, and you want to throw up but are worried you will poop your pants if you do.... one extra mile feels like another marathon!

Thousands of people lined the embankment and the approach to the Houses of Parliament; I'd love to say I enjoyed this part but am ashamed to admit that I just wanted it all to be over. 

In hindsight, I understand the selfless intention they all had to get us over the final hurdle, and I'm eternally grateful. I thought the Breast Cancer Now team were going to explode with excitement, and they gave me another much-needed reminder of what this was all for. 

The journey home was beautiful, people on the train gave up their seats as I clung onto my hypothermia blanket, and they were kind enough not to complain about the smell. 

One week on, the legs are less sore, although the toes are an attractive shade of purple, and most toenails are in the process of falling off.

It was an incredible experience, and I'm so grateful for your support of £5,000 and climbing. THANK YOU. There is still time to donate and help to fund research to help stop breast cancer from killing 1,000 women each month in the UK.

#fightlikeagirl