Vipam,
The body of a runner is up and down. Some days you feel great, other days you feel bad. It happens to the most consistent and steady runners. It happens to the olympic champ, the local road runners, it happens to me and even to you! It's called an off race also known as a bad race.
I know one thing, most successful runners move on rather quickly after an off performance. They don't dwell on bad performances and tend to always keep their focus on the big picture.