It was just as well, because it meant that I passed through the finish line about 15 minutes before the first bombing. 

I was on my way back to my hotel room at the Westin Hotel, just metres from the finish line, and my sister, who is with me, had just left the spectator crowd right at the site of the second bombing minutes before.

I have never heard a noise like these explosions... it stopped the excited crowds in their tracks. 

There was no doubting that they were explosions and close to the finish site, but there was much confusion among everyone. 

Almost everyone started using their phones, trying to find out the news.

It took me about 15 minutes to return to my hotel room where finally the gravity of the situation was revealed.

Currently we are in a “lock down” situation, unable to leave our hotel. We are not even sure whether we can leave Boston tomorrow afternoon.

Tonight should have been hours of communal celebrations, which we were looking forward to.

Instead there is a very sombre tone ... everyone is coming to terms with a very surreal situation.

I am exhausted after an extremely early start, a huge marathon effort and emotionally drained after the recent events. Social networking means that so many of the people, friends, family, colleagues and clients who knew that I was running the Boston Marathon have been able to check in on us and make sure we are okay. 

These messages of concern, support and love have meant a lot to my sister and myself especially when we feel so isolated by distance. 

It has been such a surreal and scary situation here today in Boston, but this support has been so greatly appreciated.

*This is an edited version of an email Diane Gibney sent to The Courier yesterday following the bombings in Boston.