An impressive first-half display saw Whitchurch head into half-time 7-0 up against a side that had started the day sitting top of the table.
But the hosts rallied to score 10 unanswered second-half points to claim a narrow victory.
“It was attritional rugby, the conditions weren’t conducive to playing open rugby,” said Sturdy.
“But we were outstanding in the first half. We disrupted their lineout, defended very well and probably should have had more points on the board at half-time.
“In the second half, Stoke kicked the ball more and they chased very well. But some of our decision making was poor.
“We had some good moments of pressure, but made some bad decisions around the set-piece. We had around 50 minutes of the game, they had 20 and the last 10 was scrapped out in the middle of the park.
“We had a try that looked over the line to me, but the referee was the wrong side and he said it hadn’t been grounded.
“It was disappointing to lose and there are lessons to be learned for the next time we play in conditions like those.”
Jake Bailey bagged Whitchurch’s try with Danny Nicholas adding the conversion.
Shrewsbury are bottom of the Midlands 2 West (North) table after losing 21-6 at Tamworth.
In Midlands 3 West (North), Cleobury Mortimer claimed a 32-19 success at home to Linley, while Telford Hornets crashed 40-0 at Veseyans.
Market Drayton slipped to their first Midlands 4 West (North) defeat of the season.
Drayton were left playing catch up after Trentham established a 21-5 half-time advantage.
But there was to be no comeback as the home side ran out 26-12 winners.
Drayton’s tries came from Chad Fieldhouse and Luke Walters.
Clee Hill climbed to fourth after a 25-3 success at Aldridge.
Bishops Castle & Onny Valley beat Dixonians 21-0 in Midlands 5 West (South).