Megan Penfold struggled to meet her own high standards in Saturday's Lee Valley Open.
The 12-year-old could not build on an excellent showing at the Woodford Green Open on April 5.
Penfold won the 70m hurdles in a time of 12.11, despite running into a -4.1 wind, but the Orion Harriers athlete was only up against one other competitor.
In the high jump Penfold came third, managing a height of 1.40m - some 10cm less than she had cleared the previous weekend and coach Bob Corbett said the teenager had "no spring" on the day.
The long jump provided the real disappointment for the Essex youngster, who came 14th in the event with a distance of 4.35m.
Corbett pointed out that Penfold had been feeling the effects of an ice skating sessions a couple of days before the meeting, which a big factor in her disappointing showing.